Hard chrome plated nickel and cobalt chrome platin

Hard chrome plated nickel and cobalt chrome plating on behalf of the advantages and disadvantages of iron

Hard chrome and decorative chrome is a chrome-plated, hard chrome plating is generally used more often in high temperature conditions of machinery, such as: mold. Decorative chrome As the name implies, the main purpose is to surface bright, beautiful appearance, rust, etc.

Hard chrome plating has long been a aviation parts manufacturing, maintenance and repair of the key component. For like an airplane landing gear, turbine, hydraulic and other components, chromium can provide long-term wear-resistant coating. Unfortunately, the job found for electroplating chromium electroplating factory worker would cause serious injury.

With chrome recent years the health and environmental threats awareness significantly enhanced, leading gradually to the alternative coating technology transfer. Over the past two decades, increasingly stringent environmental and health regulations, a serious blow to the domestic industry, hard chrome plating, so that about half of the electroplating workshop moved outside companies or withdraw less restrictive rural areas. 2015 most of the chrome will be replaced. Meanwhile, chromium plating has been secured the market alternatives. Thermal spraying is the most well-known alternative to hard chrome plating process has been established in the aviation industry to aviation market outside the general industrial and heavy-duty vehicle market expansion. However, thermal spraying is facing competition from chrome with some of the same technology competition. But the thermal spraying can not be effectively spray inner hole, expensive equipment. Nickel-cobalt alloy has the following advantages:

a) coating adhesive power: b) simple process control: c) high productivity d) require small power e) can not be completely obscured: As the plating workpiece to be fully immersed in the plating bath, the local workpiece without plating surface will also be electroplated, still need processing. Or insulation plating

f) Good anti-erosion ability

g) plating will not be formed at corners or sharp edges summary, lead bonding is not strong.

h) does not affect the plating bath contaminants electrical conductivity of the solution and other plating process parameters.

i) maintenance and treatment of electroplating draining low cost.

The key is environmentally friendly.

Hard chrome is a better way to increase the surface hardness method, but many of its advantages and disadvantages, so a lot of cases, no use.

Hard Chrome Pros:

A good surface finish,

Two, will not rust, there will not be a little rusty;

Third, the plating process Zhongyuan part distortion.

Fourth, if the part size is not in place, you can add Jisi chromium to size.

Fifth, the surface is beautiful. Etc.

Hard Chrome Disadvantages:

A high price, not only plated high cost, but even after plating reprocessing.

Second, the surface is not suitable for more complex parts,

Third, the thickness is too thin, generally only about 0.05-0.15mm,

Fourth, some of the parts of the surface finish requirements are relatively high.

a) coating adhesion is not strong: in particular, with iron-based materials (such as iron) bonding is not strong, mainly because there were serious plating microcracks. Although the plating process helps to eliminate residual stress crazing, but micro-crack excessively, especially to the base from the surface micro-cracking occurs, it will cause separation of the plating layer and the substrate.

b) process control problem: it is hard to get through the process control variables can be dependent on, the plating layer repeatable, the castings are immersed in the plating bath, the iron will filter out effects of the plating solution conductivity.

c) low productivity: Average thickness of 0.0254mm plating layer, the construction lasted 1h.

d) require large power supply: general 645mm2 workpiece plating, need 14 ~ 16W power supply.

e) can not be completely obscured: As the plating workpiece to be fully immersed in the plating bath, the partial surface of the workpiece without plating will also be electroplated and need further processing.

f) Anti-erosion poor: coating the plating process cause some corrosive medium crazing penetrate into the base material.

g) plating: in the corner or sharp edge formed nodules, resulting adhesive is not strong.

h) plating bath contaminants: the solution will affect the electrical conductivity and other parameters of the plating process.

i) Maintenance and draining the high cost of treatment of electroplating.

Biggest drawback is the pollution of the environment.