中北大学本科生毕业设计论文外文翻译
毕业设计外文文献翻译

毕业设计(论文)外文资料翻译系别:专业:班级:姓名:学号:外文出处:附件: 1. 原文; 2. 译文2013年03月附件一:A Rapidly Deployable Manipulator SystemChristiaan J.J. Paredis, H. Benjamin Brown, Pradeep K. KhoslaAbstract:A rapidly deployable manipulator system combines the flexibility of reconfigurable modular hardware with modular programming tools, allowing the user to rapidly create a manipulator which is custom-tailored for a given task. This article describes two main aspects of such a system, namely, the Reconfigurable Modular Manipulator System (RMMS)hardware and the corresponding control software.1 IntroductionRobot manipulators can be easily reprogrammed to perform different tasks, yet the range of tasks that can be performed by a manipulator is limited by mechanicalstructure.Forexample, a manipulator well-suited for precise movement across the top of a table would probably no be capable of lifting heavy objects in the vertical direction. Therefore, to perform a given task,one needs to choose a manipulator with an appropriate mechanical structure.We propose the concept of a rapidly deployable manipulator system to address the above mentioned shortcomings of fixed configuration manipulators. As is illustrated in Figure 1, a rapidly deployable manipulator system consists of software and hardware that allow the user to rapidly build and program a manipulator which is customtailored for a given task.The central building block of a rapidly deployable system is a Reconfigurable Modular Manipulator System (RMMS). The RMMS utilizes a stock of interchangeable link and joint modules of various sizes and performance specifications. One such module is shown in Figure 2. By combining these general purpose modules, a wide range of special purpose manipulators can be assembled. Recently, there has been considerable interest in the idea of modular manipulators [2, 4, 5, 7, 9, 10, 14], for research applications as well as for industrial applications. However, most of these systems lack the property of reconfigurability, which is key to the concept of rapidly deployable systems. The RMMS is particularly easy toreconfigure thanks to its integrated quick-coupling connectors described in Section 3.Effective use of the RMMS requires, Task Based Design software. This software takes as input descriptions of the task and of the available manipulator modules; it generates as output a modular assembly configuration optimally suited to perform the given task. Several different approaches have been used successfully to solve simpli-fied instances of this complicated problem.A third important building block of a rapidly deployable manipulator system is a framework for the generation of control software. To reduce the complexity of softwaregeneration for real-time sensor-based control systems, a software paradigm called software assembly has been proposed in the Advanced Manipulators Laboratory at CMU.This paradigm combines the concept of reusable and reconfigurable software components, as is supported by the Chimera real-time operating system [15], with a graphical user interface and a visual programming language, implemented in OnikaA lthough the software assembly paradigm provides thesoftware infrastructure for rapidly programming manipulator systems, it does not solve the programming problem itself. Explicit programming of sensor-based manipulator systems is cumbersome due to the extensive amount of detail which must be specified for the robot to perform the task. The software synthesis problem for sensor-based robots can be simplified dramatically, by providing robust robotic skills, that is, encapsulated strategies for accomplishing common tasks in the robots task domain [11]. Such robotic skills can then be used at the task level planning stage without having to consider any of the low-level detailsAs an example of the use of a rapidly deployable system,consider a manipulator in a nuclear environment where it must inspect material and space for radioactive contamination, or assemble and repair equipment. In such an environment, widely varied kinematic (e.g., workspace) and dynamic (e.g., speed, payload) performance is required, and these requirements may not be known a priori. Instead of preparing a large set of different manipulators to accomplish these tasks—an expensive solution—one can use a rapidly deployable manipulator system. Consider the following scenario: as soon as a specific task is identified, the task based design software determinesthe task. This optimal configuration is thenassembled from the RMMS modules by a human or, in the future, possibly by anothermanipulator. The resulting manipulator is rapidly programmed by using the software assembly paradigm and our library of robotic skills. Finally,the manipulator is deployed to perform its task.Although such a scenario is still futuristic, the development of the reconfigurable modular manipulator system, described in this paper, is a major step forward towards our goal of a rapidly deployable manipulator system.Our approach could form the basis for the next generation of autonomous manipulators, in which the traditional notion of sensor-based autonomy is extended to configuration-based autonomy. Indeed, although a deployed system can have all the sensory and planning information it needs, it may still not be able to accomplish its task because the task is beyond the system’s physical capabilities. A rapidly deployable system, on the other hand, could adapt its physical capabilities based on task specifications and, with advanced sensing, control, and planning strategies, accomplish the task autonomously.2 Design of self-contained hardware modulesIn most industrial manipulators, the controller is a separate unit housing the sensor interfaces, power amplifiers, and control processors for all the joints of the manipulator.A large number of wires is necessary to connect this control unit with the sensors, actuators and brakes located in each of the joints of the manipulator. The large number of electrical connections and the non-extensible nature of such a system layout make it infeasible for modular manipulators. The solution we propose is to distribute the control hardware to each individual module of the manipulator. These modules then become self-contained units which include sensors, an actuator, a brake, a transmission, a sensor interface, a motor amplifier, and a communication interface, as is illustrated in Figure 3. As a result, only six wires are requiredfor power distribution and data communication.2.1 Mechanical designThe goal of the RMMS project is to have a wide variety of hardware modules available. So far, we have built four kinds of modules: the manipulator base, a link module, three pivot joint modules (one of which is shown in Figure 2), and one rotate joint module. The base module and the link module have no degrees-of-freedom; the joint modules have onedegree-of-freedom each. The mechanical design of the joint modules compactly fits aDC-motor, a fail-safe brake, a tachometer, a harmonic drive and a resolver.The pivot and rotate joint modules use different outside housings to provide the right-angle or in-line configuration respectively, but are identical internally. Figure 4 shows in cross-section the internal structure of a pivot joint. Each joint module includes a DC torque motor and 100:1 harmonic-drive speed reducer, and is rated at a maximum speed of 1.5rad/s and maximum torque of 270Nm. Each module has a mass of approximately 10.7kg. A single, compact, X-type bearing connects the two joint halves and provides the needed overturning rigidity. A hollow motor shaft passes through all the rotary components, and provides achannel for passage of cabling with minimal flexing.2.2 Electronic designThe custom-designed on-board electronics are also designed according to the principle of modularity. Each RMMS module contains a motherboard which provides the basic functionality and onto which daughtercards can be stacked to add module specific functionality.The motherboard consists of a Siemens 80C166 microcontroller, 64K of ROM, 64K of RAM, an SMC COM20020 universal local area network controller with an RS-485 driver, and an RS-232 driver. The function of the motherboard is to establish communication with the host interface via an RS-485 bus and to perform the lowlevel control of the module, as is explained in more detail in Section 4. The RS-232 serial bus driver allows for simple diagnostics and software prototyping.A stacking connector permits the addition of an indefinite number of daughtercards with various functions, such as sensor interfaces, motor controllers, RAM expansion etc. In our current implementation, only modules with actuators include a daughtercard. This card contains a 16 bit resolver to digital converter, a 12 bit A/D converter to interface with the tachometer, and a 12 bit D/A converter to control the motor amplifier; we have used an ofthe-shelf motor amplifier (Galil Motion Control model SSA-8/80) to drive the DC-motor. For modules with more than one degree-of-freedom, for instance a wrist module, more than one such daughtercard can be stacked onto the same motherboard.3 Integrated quick-coupling connectorsTo make a modular manipulator be reconfigurable, it is necessary that the modules can be easily connected with each other. We have developed a quick-coupling mechanism with which a secure mechanical connection between modules can be achieved by simply turning a ring handtight; no tools are required. As shown in Figure 5, keyed flanges provide precise registration of the two modules. Turning of the locking collar on the male end produces two distinct motions: first the fingers of the locking ring rotate (with the collar) about 22.5 degrees and capture the fingers on the flanges; second, the collar rotates relative to the locking ring, while a cam mechanism forces the fingers inward to securely grip the mating flanges. A ball- transfer mechanism between the collar and locking ring automatically produces this sequence of motions.At the same time the mechanical connection is made,pneumatic and electronic connections are also established. Inside the locking ring is a modular connector that has 30 male electrical pins plus a pneumatic coupler in the middle. These correspond to matching female components on the mating connector. Sets of pins are wired in parallel to carry the 72V-25A power for motors and brakes, and 48V–6A power for the electronics. Additional pins carry signals for two RS-485 serial communication busses and four video busses. A plastic guide collar plus six alignment pins prevent damage to the connector pins and assure proper alignment. The plastic block holding the female pins can rotate in the housing to accommodate the eight different possible connection orientations (8@45 degrees). The relative orientation is automatically registered by means of an infrared LED in the female connector and eight photodetectors in the male connector.4 ARMbus communication systemEach of the modules of the RMMS communicates with a VME-based host interface over a local area network called the ARMbus; each module is a node of the network. The communication is done in a serial fashion over an RS-485 bus which runs through the length of the manipulator. We use the ARCNET protocol [1] implemented on a dedicated IC (SMC COM20020). ARCNET is a deterministic token-passing network scheme which avoids network collisions and guarantees each node its time to access the network. Blocks ofinformation called packets may be sent from any node on the network to any one of the other nodes, or to all nodes simultaneously (broadcast). Each node may send one packet each time it gets the token. The maximum network throughput is 5Mb/s.The first node of the network resides on the host interface card, as is depicted in Figure 6. In addition to a VME address decoder, this card contains essentially the same hardware one can find on a module motherboard. The communication between the VME side of the card and the ARCNET side occurs through dual-port RAM.There are two kinds of data passed over the local area network. During the manipulator initialization phase, the modules connect to the network one by one, starting at the base and ending at the end-effector. On joining the network, each module sends a data-packet to the host interface containing its serial number and its relative orientation with respect to the previous module. This information allows us to automatically determine the current manipulator configuration.During the operation phase, the host interface communicates with each of the nodes at 400Hz. The data that is exchanged depends on the control mode—centralized or distributed. In centralized control mode, the torques for all the joints are computed on the VME-based real-time processing unit (RTPU), assembled into a data-packet by the microcontroller on the host interface card and broadcast over the ARMbus to all the nodes of the network. Each node extracts its torque value from the packet and replies by sending a data-packet containing the resolver and tachometer readings. In distributed control mode, on the other hand, the host computer broadcasts the desired joint values and feed-forward torques. Locally, in each module, the control loop can then be closed at a frequency much higher than 400Hz. The modules still send sensor readings back to the host interface to be used in the computation of the subsequent feed-forward torque.5 Modular and reconfigurable control softwareThe control software for the RMMS has been developed using the Chimera real-time operating system, which supports reconfigurable and reusable software components [15]. The software components used to control the RMMS are listed in Table 1. The trjjline, dls, and grav_comp components require the knowledge of certain configuration dependent parametersof the RMMS, such as the number of degrees-of-freedom, the Denavit-Hartenberg parameters etc. During the initialization phase, the RMMS interface establishes contact with each of the hardware modules to determine automatically which modules are being used and in which order and orientation they have been assembled. For each module, a data file with a parametric model is read. By combining this information for all the modules, kinematic and dynamic models of the entire manipulator are built.After the initialization, the rmms software component operates in a distributed control mode in which the microcontrollers of each of the RMMS modules perform PID control locally at 1900Hz. The communication between the modules and the host interface is at 400Hz, which can differ from the cycle frequency of the rmms software component. Since we use a triple buffer mechanism [16] for the communication through the dual-port RAM on the ARMbus host interface, no synchronization or handshaking is necessary.Because closed form inverse kinematics do not exist for all possible RMMS configurations, we use a damped least-squares kinematic controller to do the inverse kinematics computation numerically..6 Seamless integration of simulationTo assist the user in evaluating whether an RMMS con- figuration can successfully complete a given task, we have built a simulator. The simulator is based on the TeleGrip robot simulation software from Deneb Inc., and runs on an SGI Crimson which is connected with the real-time processing unit through a Bit3 VME-to-VME adaptor, as is shown in Figure 6.A graphical user interface allows the user to assemble simulated RMMS configurations very much like assembling the real hardware. Completed configurations can be tested and programmed using the TeleGrip functions for robot devices. The configurations can also be interfaced with the Chimera real-time softwarerunning on the same RTPUs used to control the actual hardware. As a result, it is possible to evaluate not only the movements of the manipulator but also the realtime CPU usage and load balancing. Figure 7 shows an RMMS simulation compared with the actual task execution.7 SummaryWe have developed a Reconfigurable Modular Manipulator System which currently consists of six hardware modules, with a total of four degrees-of-freedom. These modules can be assembled in a large number of different configurations to tailor the kinematic and dynamic properties of the manipulator to the task at hand. The control software for the RMMS automatically adapts to the assembly configuration by building kinematic and dynamic models of the manipulator; this is totally transparent to the user. To assist the user in evaluating whether a manipulator configuration is well suited for a given task, we have also built a simulator.AcknowledgmentThis research was funded in part by DOE under grant DE-F902-89ER14042, by Sandia National Laboratories under contract AL-3020, by the Department of Electrical and Computer Engineering, and by The Robotics Institute, Carnegie Mellon University.The authors would also like to thank Randy Casciola, Mark DeLouis, Eric Hoffman, and Jim Moody for their valuable contributions to the design of the RMMS system.附件二:可迅速布置的机械手系统作者:Christiaan J.J. Paredis, H. Benjamin Brown, Pradeep K. Khosla摘要:一个迅速可部署的机械手系统,可以使再组合的标准化的硬件的灵活性用标准化的编程工具结合,允许用户迅速建立为一项规定的任务来通常地控制机械手。
毕业设计(论文)外文文献翻译》

毕业设计(论文)外文文献翻译(本科学生用)题目:低成本激光距离传感器学生姓名:任铎学号:130112021126 学部(系): 光电信息科学与工程专业年级: 13光信(2)班指导教师:张静职称或学位:讲师20 17 年 02 月 25 日结构化线路设备。
这些设备使用光条激光器和偏移相机来确定一组点的范围。
因为激光能量在线上传播,所以难以实现精确的范围,特别是在存在环境光的情况下或且它们的成本和机械脆性将保持高。
点模块。
像Revo设备一样,存在可能被旋转以实现大Sharp IR传感器[9],它使用位置敏感器件(PSDq = fs. (1)∑ I (i) i/ ∑ I (i) .i i6m. I. Iat 6 m, angularthe most common tasks for mobile robots is to 6. 4000readings per second (scans up to 10 Hz) make a mapand navigate in an environment. To do so, 7. Small size,low power (< 2W) the robot needs to sense itsenvironment in an efficient 8. Standard, commercially-available components. way, looking out to somedistance to find obstacles and 9. Low cost: $30 cost tobuild. build a map that is useful for performing taskssuch asvacuuming or delivery. These characteristics make theRevo suitable for consumer While there are manysensors that could be used, laser products, and open the way for high-performance, low-distance sensors are currently the standard sensor in cost mobile robots. Although all of the Revo technologies indoor and outdoor mobile robots. The main reason is the have been used in other devices, to date no-one has utility of the data: an LDS returns distance to objects in its realized that they could be combined to make a low-cost, field of view, unlike (for example) vision sensors, which high-performance sensor. Achieving the above criteria need complicated and error-prone processing before required innovations in design, algorithms, and distances are measured. And unlike other distance sensors integration. The key elements of the Revolenscurve.Figure II-6 Maximum pulse power and Maximum Permissiblebased outer drive has been tested in continuous use over。
毕业论文外文翻译要求

毕业论文外文翻译要求The requirements for the translation of the foreign language section of the graduation thesis are as follows:1. Word Count: The translated foreign language section should be around 700 words.2. Accuracy: Ensure the translated text accurately reflects the original meaning and intent of the foreign language source. It should be free from any substantial errors or omissions.3. Language Style: Maintain a professional and academic tone throughout the translation. Use appropriate terminology and vocabulary to convey the subject matter effectively.4. Grammar and Syntax: Follow the rules of grammar and syntax in the target language. Pay attention to sentence structure, verb agreement, and correct word order.5. Consistency: Ensure consistency throughout the translation. Use the same terminology and style for recurring words, phrases, and concepts.6. Flow and Cohesion: Maintain the flow and cohesion of the translated text. Use appropriate transition words and phrases to connect ideas and ensure a smooth reading experience.7. Cultural Sensitivity: Take into account any cultural nuances or references that might require adaptation or explanation in the translated text. Consider the target audience's cultural backgroundand adapt the language accordingly.8. Formatting: Format the translated text to match the formatting requirements of the graduation thesis. Ensure proper indentation, paragraph spacing, and font style.9. Proofreading: Thoroughly proofread the translated text to identify and correct any typos, spelling errors, or grammatical mistakes.10. Delivery: Submit the translated foreign language section within the specified deadline. Provide the translated text in a compatible format, such as a Word document or PDF file.By adhering to these requirements, the translated foreign language section of the graduation thesis will meet the desired standards of quality and accuracy.。
中北大学毕业设计外文翻译

气动加热及应力的数据模拟:化学气相沉积硫化锌高超音速飞行器摘要:超音速飞行器在红外窗口设计方面,对气动力的强烈程度和气动加热的严重程度要求更为严格。
本文使用有限元分析提出基于热应力场的分布在红外窗口流场对超音速飞行器的研究。
评估提供了理论指导气动加热的影响和力量在红外窗口材料。
气动热流从Mach 3 - 6马赫航班在15公里的高度在标准大气通过流场分析。
温度和压力反应然后调查下常数传热系数边界条件对不同马赫数。
数值结果表明,最大应力高于材料强度在6马赫,这意味着材料可能出现的失败。
的最大应力和温度低于熔点的材料强度和在其他情况下,所以材料安全的。
关键词:化学气相沉积(CVD)的硫化锌,红外窗口材料,热应激反应,高超音速车辆doi:10.1631 / jzus.A1300341 文档代码:A CLC数量:V211简介飞机和航天器结构设计超音速和高超音速飞行是接受在发射和严重的气动加热再入阶段的操作,这是所致的空气边界层逐渐减慢(阮et al .,2010)。
因此,所有车辆的外部表面加热。
这将会导致不均匀的瞬态温度生产动态热应力和变形。
因此,高加热与冲击前缘是车辆的重要问题设计。
除了表面的融化和消融飞机空气动力学可以摄动,导致不可接受的飞行轨迹的偏差。
另一个问题信号折射穿过震惊吗热气体层在汽车前面的头(萨拉瓦南et al .,2009)。
近年来,已经有了意义投资发展的高超音速汽车技术。
高超音速飞行开始1949年2月,当一个女军团(WAC)下士从我们捕获的v - 2火箭点燃火箭(太阳和吴,2003)。
后来,广泛的数值分析(Jain和海斯,2004;Di Clemente et al .,2009;Gerdroodbary Hosseinalipour,2010)压力、传热和表面温度定或不稳定传热边界层高超音速流。
尽管一些飞行实验也进行了(Di Clemente等,2007;马里尼et al .,2007)收购空气动力学加热在飞行条来评估这些数据预测方法,飞行数据并不适合完成验证。
毕设设计类外文翻译

Interior Design Supports Art Education: A Case StudyInterior design, as a field of study, is a rapidly growing area of interest – particularly for teenagers in the United States. Part of this interest stems from the proliferation ofdesign-related reality shows available through television media. Some art educators and curriculum specialists in the nation perceive the study of interior spaces as a ‘practical application’ of the arts.This article discusses an experiential design problem, originally used in higher education interior design studio courses that was modified and shared with students in third grade to address national academic standards. Later, this same project was modified for use with high school students in the educator’s community a nd with international design students in South Korea.Lastly, the project was presented in a workshop to art education students at a higher education institution. The project was modified to address (1) the age group level and (2) a topic relevant to the audience. Goals of the design project were: (1) to explore creative problem-solving, (2) to explore the application of design elements and principles, and (3) to increase student understanding of spatial relationships within an interior environment. Findings indicate that the project supported several visual art standards, including perception and community. This project may be of interest to current and future art educators and others interested in the potential of interior design content supporting art education.IntroductionThe design of interior spaces is a growing area of interest in the United States. Studies indicate that people spend 90 per cent of their time indoors, thereby making the quality design of interiors critical to the health and welfare of the population. Youth have been unconsciously encouraged since their childhood to develop awareness of their personal interior spaces and furnishings through popular storybooks they read that introduce the awareness of scale, proportion and ergonomics at a very young age (e.g. Three Little Bears and Alice in Wonderland). More recently, teens in the United States have become unexpectedly ‘hooked’ on design related reality shows such as Trading Spaces, Changing Rooms and Design on a Dime. Although Trading Spaces was originally intended for adults, according to the Wall Street Journal article titled ‘The Teen-Room Makeover’ (18 October 2002) the audience has more than 125,000 viewers aged 12 to 17 [1]. In support of that finding, a survey conducted in 2003 for a national chain of hardware stores discovered 65 per cent of teens said they have watched home improvement-related television shows [2].Teens seemingly have a growing interest in the design of interior spaces.In the United States in 2002, a qualitative study was developed to determine if interior design subject-matter could support national academic standards in elementary and secondary schools (kindergarten – twelfth grade) [3]. Findings of the study indicated that art educators and curriculum specialists perceived interior design to be supportive in meeting their standards as a type of ‘practical application’ of the arts. Perceptions of the curriculum specialists indicated they were looking for new ways to interpret fine art standards in their existing curriculum and that interior design offered one solution. As a result, the researcher, who was an interior design educator, was encouraged to identify and develop a project or lesson plan that could introduce children and youth to the importance of well-designed interior spaces yet support an art education standard in the nation.This article discusses an experiential interior design project that was modified from an exercise used in the freshman and sophomore college studio classes and shared with students in third grade, high school, and with international students in South Korea by this interior design educator. The educator was later invited to present this project to art education teachers at her university. The project supported several school district visual art standards, including perception and community. It was modified to address (1) the age group level and (2) a topic relevant to the audience. Goals of the design project were: (1) to explore creative problem solving, (2) to explore the application of design elements and principles, and (3) to increase student understanding of spatial relationships within an interior environment. This project may be of interest to current and future art educators and others interested in the potential of interior design content supporting visual art standards.Review of literatureThe review of literature briefly discusses (1) experiential learning theory, (2) findings from a qualitative study involving art educators, and (3) the interior design link with art education. The interior design project description and process of application will follow.Experiential learningExperiential learning theory, as an application of cognitive/perceptual models, is a tool toenhance the cognitive process of students. Specifically, the experiential learning cycleinvolves a concrete experience that leads to observations and reflections then to formation of abstract concepts and generalisations, before finally testing implications from concepts in new situations [4].The Association for Experiential Education defines experiential education astheprocess by which a learner constructs knowledge, skill and value from direct experience [5]. Drengson [6] defines experiential education as the process of practical engagement withconcepts and skills applied in a practical setting and delivered through physical and practical mental activity.One of the key components to enhance student learning is reflection. Dewey [7] suggests that to have meaning, an experience must be combined with thought. Kolb [8] suggests that reflections can offer a potential source of powerful data to link theory to practice. The mental engagement of an experiential learner can involve questioning, investigation, experimentation, curiosity, problem-solving, assuming responsibility, creativity and the construction of meaning [9].Experiential learning offers the spontaneous opportunity for learning, whether from unplanned moments, natural consequences, mistakes or successes [10]. Holistically, it involves not only the cognitive but also any combination of the senses, the emotions, and the physical [11].Qualitative study involving art educatorsIn 2001, a study was conducted to determine if interior design may be supportive tokindergarten – twelfth grade (K–12) teachers in meeting national academic standards,including the arts [12]. To understand perceptions of experts in interior design and elementary and secondary education, five focus group session sand six personal interviews were conducted with interior design educators, practitioners,K–12 teachers (elementary, junior high, and high school levels), national standards curriculum specialists (local and state level), and school-to-career curriculum specialists from June 2001 to April 2002[13].Focus group findings indicated that K–12teachers, at both elementary and secondary levels, felt that interior design could be supportive in meeting visual art standards because youth are frequently analysing their personal and public spaces. Participants described specific examples of interior design materials they currently needed in their course work to include: examples of good and bad interior spaces, information about elements and principles of design as they relate to interior spaces, and hands-on col our wheels of sturdy materials. In addition they requested that the materials be low cost, stimulating,‘touchable’,recyclable, self-contained, and fun. Lesson plans the visual art teachers suggested included:• reinvention of the ‘shoe box’ projec t;• development of well-known stories (The Three Pigs, Three Little Bears, and Alice in Wonderland) into space models to teach proportion and scale. In addition, it was suggestedthe following lesson plan: use of Goldilocks story to analyse ‘client or consumer needs’;• use of a Dr Seuss story (literary passage) to generate a conceptual model that enhances creativity;• study of cultural spaces at the junior high level that would enhance study of personal expression of identity in interiors [14].The visual arts curriculum specialists indicated hat interior design –as a ‘practical application’ should be introduced in elementary levels where there is a ‘small window of opportunity’ to give good information about the visual arts. See Table 1 fo r an example of the visual art standards in kindergarten – third grade levels. One visual art specialist advocated that the design process was more important to teach than a particular design method. He suggested moving students from designing personal spaces – and the study of elements and principles of design – in elementary levels to the analysis of private and public spaces in the junior high level. Then the high school levels could be reserved for additional indepth Exploration.Today, junior high and high school students are quite attracted to design-related reality shows. Over the last five years, the number of designrelated television shows has increased dramatically [15]. Why are these shows so attractive to teens and young adults? Rodriguez [16]has suggested that this interest is linked to the teens need for expression of self andself-identity.An individual’s unique identity is established through personalisation of space, which is critical to overall development of self [17]. Developing a sense of self involves the use of symbols to communicate to others one’s personal underlying identity.Interior design link with art educationIt is not common for interior design to be linked with art education in K–12 grade levels in the United States. However, the Foundation for Interior Design EducationResearch[18]standards and guidelines – the accreditation organization for higher education interior design programmes in the nation – reveal that there are many shared areas between visual arts and interior design (e.g.elements and principles of design).Rasmussen and Wright [19]advocate the need for a new model for art education. The new model should offer youth an aesthetic education that does more than just serve the traditional concerns of established arts curriculum. Experiences indicate that young people try to make sense of their own lives by creating contextual understanding through actively, and intentionally, making connections to signs, perceptions and experiences. This is a challenge to develop a new art education model that creates a balance between social andcontextual needs, knowledge of young people, and theaesthetic medium itself.The study of interior spaces offers one such context for learning in the physical environment.People spend 90 per cent of their time in interior spaces [20]. Youth consciously or unconsciously, analyse and respond to their near environment. They also learn best if they understand why they are learning what they are learning. Application of design and art to everyday life can assist in making connections in student learning, and develop more awareness of good design as well as an appreciation of the arts. Youth need theopportunity to learn more about design and human behavior so they can learn they have choices about how supportive their environments can be. Children can [determine] how design influences their behaviors; howdesign can be used to manipulate behavior; how design can encourage or discourage conversation, establish status, put people in power positions, increase or decrease anxiety [21].Therefore, based on (1) the experiential learning theoretical underpinnings, (2) recommendations made by art educators and curriculum specialists, and (3) a call for a new ways of teaching art education, an interior design educator at a higher education institution modified an experiential design project that involved the use of elements and principles of design and an opportunity for self-expression of personal spaces. The designproblem of the personal space was changed based on the grade level.Case study project descriptionAlthough art educators and curriculum specialists perceived that interior design content could be supportive to visual art standards, it was determined that a case study project needed to be developed and presented to various grade levels. It was also determined that a conceptual model of interior spaces should be used toenhance student creativity and exploration rather than a finite model that would offer too many rules and boundaries. Project descriptionThe experiential interior design project involved the construction of athree-dimensional concept model using 44 triangular and rectangular pieces of cardstock (stiff) paper in a neutral colour [22]. The objective was to discover, manipulate and create interior spaces based on a given design problem (e.g. design your space station on a planet of your choice or design your home in the Rocky Mountains of Colorado). The purpose ofthe project was to encourage students to design a conceptual structure from the interior out, keep-ing in mind the function of the building. The student’s model had to incorporate a minimum of six spaces and three levels to encourage vertical as well as horizontal volumes. All 44 pieces of cardstock had to be used in the finished model, which sometimes posed achallenge to the youth. The cardstock pieces could not be ripped, torn, or pierced. However, they could be bent and shapedaccording to the whim of the student.Flow from one space to another and one level to another was emphasized. The decision-making design process was explained and encouraged.Outcomes consisted of a three-dimensional abstract model which, if successfully executed, demonstrated the break-down of traditional spatial paradigms. Design problemsEach student grade level was given a different design problem based on the academic standards that were to be met in that class. In some cases, several academic standards were addressed at the same time. Two national standards for visual arts in the United States were selected to be supported with this project: communication and perception. The communication standard indicates that students in kindergarten – third grade should recognise the use of the visual arts as a means of communication (e.g. select and use visual images, themes and ideas in their own work). The perception standard indicates that students know, understand and apply elements of visual arts and principles of design (e.g. Identify elements and principles of design).Third grade studentsAfter procuring appropriate permission, the design educator brought volunteer college-age interior design students to the elementary school to help administer the project. Three third grade classes (twenty students in each class) had just finished a science unit on space and orbits and were studying specific visual art standards. The children were asked to design a personal space station on a planet of their choice. The goal was to help students relate the newly learned science information to something in real life (e.g. Their home), yet encourage exploration of visual arts (see Figs. 2–4).Each team of students was given the same 44 pieces of cardstock (all cut out) in a plastic bag, a cardboard base (15” x 15” square) on which to build the model, and cellophane tape to use in constructing the model. To enhance reflection of this experiential project, each team of three students was asked to give a two-minute verbal presentation in front of the class on their finished model. In this manner, they could discuss their design solution and the design educator could assess their use of creativity through design elements and principles.The college students and design educator rotated through the three classrooms of students to answer questions, encourage use of design elements and principles, and applaud their creative exploration. The third grade teachers assisted in supporting the structure of the class and encouraging shy students who were reluctant to begin.It was interesting to observe that the children rarely built the models on their provided classroom tables. Instead,they moved to the floor space, located the base for the model in between team members, and began construction. Each team member assumed a role in the process. One team member seemed t o act as the ‘designer’, one as the ‘builder/construction crew’ and the last as the ‘supplier’ of materials. Students excitedlydiscussed the positioning of the triangular pieces of cardstock in their model, their rooms in their space stations, and the different ways to turn the model to create different vantage points.The teams of third graders had one hour to complete the models. Then their verbal presentations began, interspersed with questions and comments from the design educator and third grade teachers. Informal observations indicatedthat application of design elements and principles was strong – perhaps due to the consistent rectangular and triangular shapes that had been provided – thereby supporting the visual arts perception standard. Manipulation of shapes was innovative. Line, shape and form were used to provide movement through adjoining spaces and offered a sense of verticality. Interior volumes were created that supported human behaveour in interior spaces. For example, one team’s presentation discussed how their space station boasted an exercise room with trampolines to strengthen human muscles that weakened as a result of zero gravity in outer space. The communication standard was supported in their finished models in a couple ways. First there was a theme of design as it relates to protection from foreign objects. For example, one team’s space station on Saturn incorporated a force field to protect it from flying rocks. Other visual themes of security and safety evoked the implementation of security cameras, alien detectors, missile launchers, telescope laboratories, control stations and transport rooms. Another visual theme related to circulation. Circulation within the structure was depicted by the third graders through the use of escalators, stairs, elevators and poles. A third visual theme was unique human needs as they relate to interior spaces. Almost every team’s space station incorporated a room for their mothers! In addition, depending on the students’ personal interests, unique space station features ranged from chemical rooms to sandboxes. It was obvious in their multiple unique design solutions their use of creativity had been explored and enhanced.Evaluation and assessment that took place, after the classes were dismissed, indicated that the third grade teachers perceived that this experiential design project supported the visual arts standards in both the communication and perception components as well as the third grade science academic standard concerning space and orbits. In addition, the experiential component of the project had unexpected results when certain quiet, unassuming students in the class became animated and highly engaged in learning. One teacher shared her excitement with the design educator about a new connection that wasformed with one of students that she had not been able to connect with before the design exercise.High school studentsAfter the case study with the third grade students, it was determined to offer this project to high school students. Diversity students in a nearby community were invited to attend a complimentary design workshop at a local library. The interior design educator was asked to present a design problem that would relate to arteducation (see Figs. 6–8).Their problem was to use the same experiential project and shapes to design and construct a conceptual model of their new home or cabin in the Rocky Mountain region. The same project constraints existed. Due to the students’ ages, discussions took place prior to the exercise about innovative problem-solving, the exploration of creativity and the elements and principles of design used within the design process. Some of these elements and principles included:Scale. Awareness of human scale was addressed to develop understanding of proportion and scale of the structure and interior spaces. Shape. Triangular shapes were deliberately selected to encourage students to break paradigms of rectangular interior spaces.Colour. The cardstock pieces were of a neutral colour to enhance spatial composition rather than draw attention to colour usage or juxtaposition. Volume/Mass. The mass of thethree-dimensional model was important in communicating the use of common elements and principles of design (e.g. line, rhythm). Line. A variety of different lines (e.g. diagonal, horizontal) were investigated in the manipulation of the shapes. Space. Space was created through the manipulation of shapes. Theories of complexity, mystery and refuge within interior spaces were discussed. Informal assessment of the finished design models indicated that the design solutions werevery creative.Later that semester, by invitation, the same design project was taken to college students training to be art educators in a mini-workshop format. The art education students found the exercise effective in enhancing creativity and understanding how interior design can enhance understanding of visual arts.International studentsAlthough there was no intention to meet a national visual arts academic standard at a specific grade level, this same experiential design project was presented in Seoul, South Korea to college-aged international students. The design problem was to use the same 44 pieces to develop a design concept model for acommercial building in Seoul. Language translators were used to help the design educatorintroduce the project, guide the students through the process, and understand their verbal presentations at the end of the workshop.Students commented during and after the workshop how the model enhanced their visual literacy skills (they used different words) and creativity within the context of everyday life. The experiential nature of the workshop was seemingly a pleasure to them (see Figs.9–11).Discussion and conclusionThis interior design case study project was designed to be experiential in nature to enhance student learning of the visual arts. Student and teacher assessment of the various groups indicated enthusiasm for the design project because it enhanced creativity, explored multiple design solutions, related to real life, and increased their understanding of human behaviour within the context of the physical environment. Teacherassessment of the age groups indicated that the project did support visual art standards at the appropriate grade level. In addition, their assessment indicated satisfaction with the manner in which the interior design project encouraged student usage of the design elements and principles and the application of design to everyday living. Several instructors indicated that quiet and shy students in their class became engaged in the learning process, which had not been previously observed. Perception of art educators and art education students was that this project supported a variety of visual art standards such as perception and communication. This interior design case study project can be modified for various age and cultural groups and may be of interest to educators who are interested in working collaboratively with colleagues from other disciplines.Visual art programmes in the United States are being cut from the K–12 curriculum. By linking visual arts to an up-and-coming aesthetic field, such as interior design, there may be new ways to sustain and grow visual art programmes in the nation.References1. Orndoff, K. (2003) ASID American Society of Interior Designers 2003 Strategic Environment Report. Future Impact Education, p. 9.2. Levitz, S. (2004) Teens Hooked on Home Décor, London Free Press (Ontario, CA), 24 June, p. D2.3. Clemons, S. (2002) Collaborative Links with K–12: A Proposed Model Integrating Interior Design with National Education Standards, Journal of Interior Design, Vol. 28, No. 1, pp.40–8.4. Rubin, S. G. (1983) Overcoming Obstacles to Institutionalization of Experiential Learning Programs, New Directions for Experiential Learning, Vol. 20, pp. 43–54.5. Luckman, C. (1996) Defining Experiential Education, Journal of Experiential Education, Vol. 19, No. 1, pp. 6–7.6. Drengson, A. R. (1995) What Means this Experience? in Kraft, R. J. & Sokofs, M. [Eds] The Theory of Experiential Education. Boulder, CO: Association for Experiential Education, pp. 87–93.7. Dewey, J. (1916) Democracy and Education. New York: Macmillan.8. Kolb, D. A. (1984). Experiential Learning: Experience as the Sources of Learning and Development. Englewood Cliffs, NJ: Prentice-Hall.9. Luckmann, C. op. cit.10. Ibid.11. Carver, R. (1996) Theory for Practice: A Framework for Thinking about Experiential Education, Journal of Experiential Education, Vol. 19, No. 1, pp. 8–13.12. Clemons, S. op. cit.13. Ibid.14. Ibid.15. Bien, L. (2003) Renovating how-to TV Shows in a Race to Duplicate Success of ‘Trading Spaces’. The Post Standard (Syracuse, NY), 31 October, p. E1.16. Rodriguez, E. M. (2003) Starting Young, Miami Herald, 28 December, p. H–1.17. Baillie S. & Goeters, P. (1997) Home as a Developmental Environment. Proceedings of the American Association of Housing Educators, New Orleans, LA, pp. 32–6.18. Foundation of Interior Design Education Research (FIDER) home page. Available from URL: / (Accessed 4th January 2005).19. Rasmussen, B & Wright, P. (2001) The theatre workshop as educational space: How imagined reality is voiced and conceived, International Journal of Education & the Arts, Vol. 2, No. 2, pp.1–13.20. Environmental Protection Agency (2006) An Introduction to Indoor Air Quality (online). Available from URL: /iaq/ ia-intro.html (Accessed 26th September 2006).21. InformeDesign (n.d.) Implications, Vol. 1, No. 2, p. 2 (online). Available from URL: /# (Accessed 4th January 2005).22. Curfman, J. & Clemons, S. (1992) From Forty-Four Pieces to a New Spatial Paradigm, in Birdsong, C. [Ed.] Proceedings of the Interior Design Educators Council Southwest Regional Meeting, New Orleans, pp. 2–4./detail/refdetail?tablename=SJWD_U&filename=SJWD00000744102&uid=WEEvR EcwSlJHSldSdnQ0SWZDdUlMV1dWZi9tOGkyYTBaTzBVQjVYeENXYVp4MVRJQjI3cmZRYS9YRmhvdnlxazJRPT 0=$9A4hF_YAuvQ5obgVAqNKPCYcEjKensW4IQMovwHtwkF4VYPoHbKxJw!!Interior Design in Augmented Reality EnvironmentABSTRACTThis article presents an application of Augmented Realitytechnology for interior design. Plus, an Educational InteriorDesign Project is reviewed. Along with the dramatic progress ofdigital technology, virtual information techniques are alsorequired for architectural projects. Thus, the new technology ofAugmented Reality offers many advantages for digitalarchitectural design and construction fields. AR is also beingconsidered as a new design approach for interior design. In an ARenvironment, the virtual furniture can be displayed and modifiedin real-time on the screen, allowing the user to have an interactiveexperience with the virtual furniture in a real-world environment.Here, AR environment is exploited as the new workingenvironment for architects in architectural design works, and thenthey can do their work conveniently as such collaborativediscussion through AR environment. Finally, this study proposesa newmethod for applying AR technology to interior designwork, where a user can view virtual furniture and communicatewith 3D virtual furniture data using a dynamic and flexible userinterface. Plus, all the properties of the virtual furniture can beadjusted using occlusion- based interaction method for a TangibleAugmented Reality. General TermsApplications of computer science in modeling, visualization andmultimedia, graphics and imaging, computer vision, human-computerinteraction, et al.KeywordsAugmented Reality, Tangible AR, CAAD, ARToolKit, Interiordesign.1. INTRODUCTIONVisualizing how a particular table or chair will look in a roombefore it is decorated is a difficult challenge for anyone. Hence,Augmented Reality (AR) technology has been proposed forinterior design applications by few previous authors, for example,Koller, C. Wooward, A. Petrovski; K. Hirokazu, et al. The relateddevices typically include data glassesconnected to a。
毕业设计论文中英文翻译要求

毕业设计论文中英文翻译要求Graduation Thesis Translation RequirementsEnglish translation of Graduation Thesis:1. Accuracy: The English translation of the Graduation Thesis should accurately reflect the content and meaning of the original Chinese text. It should convey the same ideas and arguments as presented in the original text.2. Clarity: The translation should be clear and easy to understand. The language used should be appropriate and the sentences should be well-structured.3. Grammar and Syntax: The translation should follow the rules of English grammar and syntax. There should be no grammatical errors or awkward sentence constructions.4. Vocabulary: The translation should make use of appropriate vocabulary that is relevant to the topic of the Graduation Thesis. Technical terms and concepts should be accurately translated.5. Style: The translation should maintain the academic style and tone of the original Chinese text. It should use formal language and avoid colloquial or informal expressions.6. References: If the Graduation Thesis includes citations or references, the English translation should accurately reflectthese citations and references. The formatting of citations and references should follow the appropriate style guide.7. Proofreading: The English translation should be thoroughly proofread to ensure there are no spelling or punctuation errors. It should also be reviewed for any inconsistencies or inaccuracies.Minimum word count: The English translation of the Graduation Thesis should be at least 1200 words. This requirement ensures that the translation adequately captures the main points and arguments of the original text.It is important to note that there may be specific guidelines or requirements provided by your academic institution or supervisor for the translation of your Graduation Thesis. Please consult these guidelines and follow them accordingly.。
毕业设计外文文献翻译范文

毕业设计外文文献翻译专业学生姓名班级学号指导教师优集学院外文资料名称:Knowledge-Based Engineeri--ng Design Methodology外文资料出处:Int.J.Engng Ed.Vol.16.No.1附件: 1.外文资料翻译译文2.外文原文基于知识工程(KBE)设计方法D. E. CALKINS1.背景复杂系统的发展需要很多工程和管理方面的知识、决策,它要满足很多竞争性的要求。
设计被认为是决定产品最终形态、成本、可靠性、市场接受程度的首要因素。
高级别的工程设计和分析过程(概念设计阶段)特别重要,因为大多数的生命周期成本和整体系统的质量都在这个阶段。
产品成本的压缩最可能发生在产品设计的最初阶段。
整个生命周期阶段大约百分之七十的成本花费在概念设计阶段结束时,缩短设计周期的关键是缩短概念设计阶段,这样同时也减少了工程的重新设计工作量。
工程权衡过程中采用良好的估计和非正式的启发进行概念设计。
传统CAD工具对概念设计阶段的支持非常有限。
有必要,进行涉及多个学科的交流合作来快速进行设计分析(包括性能,成本,可靠性等)。
最后,必须能够管理大量的特定领域的知识。
解决方案是在概念设计阶段包含进更过资源,通过消除重新设计来缩短整个产品的时间。
所有这些因素都主张采取综合设计工具和环境,以在早期的综合设计阶段提供帮助。
这种集成设计工具能够使由不同学科的工程师、设计者在面对复杂的需求和约束时能够对设计意图达成共识。
那个设计工具可以让设计团队研究在更高级别上的更多配置细节。
问题就是架构一个设计工具,以满足所有这些要求。
2.虚拟(数字)原型模型现在需要是一种代表产品设计为得到一将允许一产品的早发展和评价的真实事实上原型的过程的方式。
虚拟样机将取代传统的物理样机,并允许设计工程师,研究“假设”的情况,同时反复更新他们的设计。
真正的虚拟原型,不仅代表形状和形式,即几何形状,它也代表如重量,材料,性能和制造工艺的非几何属性。
毕业论文的外文译文

毕业论文的外文译文Due to the increasing importance of communication and cooperation in today's globalized world, businesses are constantly looking for ways to improve their cross-cultural communication skills. One area where these skills are crucial is in the internationalization of companies, where firms require a deep understanding of the cultural differences in order to be successful. This requires a comprehensive understanding of not only language, but also the cultural norms and values of the target market. In this thesis, we will explore the importance of cross-cultural communication in international businesses and how it can be improved.The primary challenge in cross-cultural communication is the language barrier. While English is the dominant language in international business, many firms find that it's not enough to communicate effectively with their target market. There are cultural differences in the way people use language, as well as differences in nonverbal communication such as body language and facial expressions. For instance, in Japan, it's common to nod and smile even if one does not agree with astatement, whereas in the United States, a lack of disagreement often means agreement. These differences can lead to misunderstandings in business conversations, which can ultimately harm business relationships.In order to overcome these language barriers, companies need to invest in language training for their employees. This training should focus not only on the language itself, but also on the cultural norms and values associated with the language. For example, a Japanese training program might teach students about the concepts of harmony and respect in Japanese culture, and how these values influence the way people communicate with each other. By understanding these cultural norms, employees will be able to communicate more effectively with their Japanese counterparts.Another challenge in cross-cultural communication is understanding the cultural context of business interactions. In some cultures, business is conducted in a more formal manner, with a strong emphasis on hierarchy and protocol. In other cultures, business is more informal and relaxed. Companies need to understand these differences in order to work effectively in international markets.To overcome these context challenges, companies should incorporate cultural training into their employee training programs. Cultural training should focus on the history, customs, and traditions of the target market. It should also address the specific business practices and protocol required for success in that market.In conclusion, cross-cultural communication is a key determinant of success in international businesses. In order to succeed in foreign markets, companies must have a deep understanding of the language, cultural norms, and values of their target market. This requires a comprehensive training program that not only focuses on language skills, but also on the cultural context of business interactions. With the right training and support, companies can improve their cross-cultural communication skills and achieve success in global markets.。
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钛合金粉末激光熔敷
WEN Jialing NIU Quanfeng XU Yanmin
摘要:这篇文章旨在如何通过利用B,Si和Cr等元素提高硬度和耐磨性,利用稀土元素提高合金性能。
基于铁基合金(Fe-Cr-Ni-B-Si-Re)的实验,通过一系列的实验和综合分析,包括表面质量、频谱复合、显微硬度、显微扫描和综合评价,得到最优方案。
结果,Fe-Cr-Ni-B-Si-Re涂覆材料具有很好的性能。
关键字:激光熔敷;微观结构;合金;硬度
1 前言
激光熔敷是目前最具发展前景的表面改性技术之一,它能花费很小的代价在一种普通材料表面形成很好的性能。
从而节约稀有材料和贵重材料。
其应用前景极其广阔。
作为一种表面硬化材料,Fe-Cr-Ni-B-Si-Re是自溶性合金,在正常温度范围之内和400℃以下,它的耐磨性比WC-Ni基合金、钴基合金以及其他铁基合金都要好。
考虑到下列因素,同钴基合金、镍基合金、陶瓷相比铁合金在激光熔覆方面的优越性能,稀有元素的节约,与基体熔覆的可比性,与其他合金相比更低的成本,利用铁基进行激光熔敷具有战略性意义和重要的经济价值。
2 实验
2.1 设计目的
本文目的在于找到每种合金的最佳比例,以优化经济方案,提高激光熔敷技术,活的光滑的非氧化熔覆表面,更好的湿度效果和适当的稀释率。
用做实验的熔融包层不能有宏观和微观缺陷且耐磨硬度应大于58HRC.
2.2 样品和尺寸
实验所用样品是Q235B钢,这种钢在工业上广泛应用。
考虑到激光熔敷的特点,更大的功率密度和简便的操作,样品的尺寸定为40mm×30mm×10mm.
2.3 激光技术参数
用于实验的技术参数如下:
的最大输出功率:2KW);焦点直径:3mm;扫描速率:14.3mm/s;熔覆功率:1800W(CO
2
层厚度:0.5mm;保护气体:氩气.
2.4 合金系列,因素和建议
选择合金系列的原则:保证熔覆层的整体性能,避免破裂。
另外还需考虑成本。
合金系列选定为:Fe-Cr-Ni-B-Si-Re.
为保证实验效果,铁基合金的含碳量约为0.7%.
为保证耐磨性和硬度,需要适当加些微量元素,如B,Si,Cr.出于廉价和高性能的目的,指导和水准的选择取决于共同部件,如活塞环、汽缸盖、铰刀、模具、阀门等。
为提高合金熔覆层的韧性和合金性能,需适量添加稀土元素。
根据正交设计理论,B,Si,Cr,Re是用于调节的。
在含量选择上,可采用等差阵列。
实验采用“有四个变量和三个阶段的正交试验”。
实验根据L9(34)做九次,每种元素的含量如下:
B(1. 5%, 3%, 4. 5%), Si (2.5%,3.5%,4.5%), Cr(13%, 16.5%,20%),Re (1%,3%,5%),Ni(9%),C(约0.7%),其余是铁。
3 结果与讨论
3.1 表面质量分析
根据上面提到的实验结果,可以得到如下结论:纤维是激光熔敷中的理想粘结材料。
尽管纤维用作粘结材料会带来诸如小斑点和氧化等弊端,但是它能提高表面平整度。
在熔融的过程中,碳氢元素是引起小斑点和氧化的主要因素。
由于存在碳和氢,难免会产生气体。
气体在表面聚集和放大,并偏离熔池,破坏了氩气保护氛围,同时,导致金属液滴飞溅。
通过查找参考书,我们发现如果将粘结材料的含量提高到2%,激光熔覆质量将会更好。
为减少氧化和熔层飞溅,预先制好的涂层会受到影响。
3.2 样品分析
激光熔敷样品检测旨在了解合金变化规律以及在熔覆过程中引起变化的原因,包括快速加热和快速冷却。
碳元素的含量约为0.7%.通过使用能谱分析装置测定熔覆层成分,熔覆近似成分和涂层表明合金的转变率很高但稀释率很低。
3.3 硬度分析
用HVS-1000显微硬度测试仪进行硬度测试。
力为:2.94N(300g),持续时间:20s.测试点之间距离:0.08mm.
样品8和9的平均硬度超过1000HV.实验数据表明,尽管熔覆层厚度只有0.5mm,但是铁基合金激光熔敷的熔覆层硬度达到了一个很高的水平。
这种高硬度、无裂纹的熔覆层能高效地提高合金耐磨性。
运用公式 2.1和公式 2.2,微硬度可转换为洛氏硬度:
相关转换数据列于表1.洛氏硬度和图表所列硬度差小于HRC2.
表1 洛氏硬度
从表1可以看出,样品7,8,9的硬度超过了62HRC,超出预测硬度58HRC.另外,样品3,4,6,7,8,9也都超出了预测值。
实验结果证明,B元素在激光熔覆中显著影响硬度。
硬度测试数据表明B元素对应度的影响是最显著的,在以Fe-Cr-Ni-B-Si-RE作为粘结材料在铁基上进行激光熔敷的实验中,元素Si的影响是次要的,且Re和Cr的影响不明显。
分离出的具有高硬度的FeB相是因为B元素的重要影响。
3.4 显微结构分析
由于激光热处理温度迅速升高和降低的特性,金属在熔池中经历很短的时间就会凝固,这就造成了铁基激光熔敷的不平衡组织。
铁基激光熔敷的熔覆层中最为典型的结构
就是马氏体和残余奥氏体。
奥氏体的转化和成长决定结构的基本形状。
在液相熔池中,奥氏体首先去核。
由于快速冷却和大冷却度,核心比很高。
在激光熔覆过程中,熔池的持续时间变短,由奥氏体转变为马氏体所形成的核心形状将会提前。
结果是得到的颗粒将会非常好。
见图1,2.
图1 样品8的熔覆层组织
图2 样品9的熔覆层组织
4 结论
通过实验和一系列对在铁基表面进行激光熔敷Fe-Cr-Ni-B-Si-RE的理论分析,包括表面质量,光谱结构,显微硬度以及电镜扫描等,可得出如下结论:
a)表面质量分析表明,尽管用作粘结材料的纤维会带来诸如小斑点和氧化之类的
弊端,但它却能提高表面平整度。
关于这一点,一个很好的例子就是具有高含
量的RE样品有很好的表面平整度。
b)微观结构分析表明在激光熔覆中获得的结构是马氏体和残留奥氏体,并且样品
8,9的结构是最好的。
相当数量的马氏体和细颗粒是关键因素。
c)最佳配比:B 4.5%,Si 3.5%,Cr 13%,RE5%,Ni9%,剩余的是铁。
结构:针状马氏
体和残留奥氏体。
硬度:约69HRC.。