TL528

││?Descriptors: Plastic parts, chromium, chromium plating

Changes

After issue of June 1993, the following changes have been made:

- Part C was added

- Basic definition was written

- Specification got new arrangement

Earlier Issues

First issue: 1965-01last changes: 1993-06

1 Field of Application

This specification regulates the requirements for surfaces of chromium plated plastic parts in the following parts (see table 1):

Table 1: Overview of Performances

*) presently for these areas of application proved kinds of plastic

2Requirements

2.1Basic Definitions

Approval of first shipment and changes according to VW 011 55.

Avoidance of harmful materials according to VW 911 01.

For a thorough inspection 10 parts are required.

For all parts the following information must be transferred by the supplier:

a) Numbers of parts

b) Manufacturer of the plastic parts (who is moulding the plastic?)

c) Basic plastic material (kind of plastic, manufacturer, brand name)

d) Plating company and plating line, place

Continued on pages 2 to 5

Parties to a contract can only obtain this standard via the responsible procurement department.

e)Date of plating

f)Metal layer sequence (thicknesses, technical description according to EN 1403 and EN 12540, refer to

table 2, section 1.2)

g)Kind of the activation of the plastic surface / plating process (e.g. chromium plating colloidal convenient

activation, ionic activation, direct plating)

h)simple sketch of the arrangement of the part on the racks (with information about distances)

For the control of colour and brightness together with every lot of plated parts a test plaque (same kind of plastic material) must be plated, too (production reference sample). The colour sampling must be performed according to section 2.4.1.

2.2Labeling

Example for the designation of a chromium plated part made from ABS exhibiting mechanical stability up to 900C used for interior application:

ABS according TL 527-A, chromium plated according to TL 528-A

2.3Moulded Part

2.3.1Base Material

Plateable plastic material according to table 1.

2.3.2Structure

Plated parts must be entirely free from any cracks or blisters. The parts must be free from any interior stress which might influence adhesion or appearance of the plated metal layer. The moulder and / or the plater has to ensure the lack of any stress by suitable quality control measures.

2.3.3Surface Quality

The surface must be smooth without any flow lines, cracks, recession, craters or popped parts which might influence the appearance of ready made parts. In addition, the surface must be absolutely clean, free from any grease or sweat. It is not allowed to use any mould releasers. It is not allowed to polish the parts prior to plating.

2.4Finished Part

2.4.1Surface Quality

On the visible part of the surface the parts must exhibit mirror – like brightness without any polishing - strike structure. The position of the contact points must be invisible when the part is installed later. There must be no pores, no cracks or other faults or damage in the plated surface, which influence appearance or corrosive behaviour. Brightness and colour of the production reference sample and of plated parts (see section 2.1) either visual and /or by measuring techniques must meet the characteristics of the formerly approved reference parts.

2.4.2Compound Quality

All layers must adhere to the base material, must exhibit good adhesion between each other and must be free of any blisters.

Prior to the examination the part must be stored at room temperature. After the examination there must be no cracks, blisters, pores, no dimensional changes and no impairment of surface appearance.

2.4.3Plating Process

Until the requirements of this term of delivery are met, the supplier is free to use any plating process. The plating process and the layer thicknesses of the plated parts must correspond to the formerly approved reference parts.

2.4.4Technological Requirements for a Plated Part (refer to table 2)

3Testing Recommendations

3.1Plated Thicknesses

The thickness should be inspected at those places which were agreed during the testings of the approved reference parts. The methods described in EN ISO 1463 and in EN ISO 2177 are prevailing. Arbitral award is given after microsection.

3.2Density of Cracks and Pores

Inspection is done using a metallographic microscope at 100x magnification with perpendicular or angular light.

3.3Sawcut

The part to be inspected should have a width of approximately 1cm to be able to compare the results. The part is cut from the backside against the plated surface using a metal band saw with 22 teeth per 25mm. After cutting, an adhesive tape (e.g. Scotch No 670) with an adhesive force of 10±1N/25mm according to EN 1464 is applied and removed jerky in an anlge of 600.

3.4Cross Hatch

The cross cutting is performed as described in EN ISO 2409 (3mm). Here, a cutting knife is used e.g. Edding Cutter M9 purchased from BLB Omnilab.

3.5Cross Cutting

Those parts where cross hatch cannot be performed due to geometrical reasons, can be inspected using the cross cut test. A knife is used as described in section 3.4. Performance and adhesive tape as described in section 3.3, paragraph 2.

4Documents In Force

VW 011 55,Fahrzeug – Zulieferteile allgemein; Genehmigung von Erstlieferung und ?nderung Common Car Parts; Approval of First Supply and Changes

VW 911 01,Umweltnorm Fahrzeug, Fahrzeugteile, Werkstoffe, Betriebsstoffe;

Schadstoffvermeidung

Environmental Standard for Cars, Car Parts, Materials, Operating Supply;

Avoidance of Noxious Materials

PV 1058,Verchromte Oberfl?chen, Bestimmung des Chromri?netzes

Chromium Plated Surfaces, Inspection of the Chromium Crack System

PV 1200,Klimawechseltest; Aggregate, Bauelemente, Systeme, Halbzeuge

Climate Cycle Testing; Aggregates, Elements, Systems, Semi-finished Products PV 1210,Karosserie; Korrosionsprüfung

Car Body; Corrosion Testing

PV 2005Fahrzeugteile, Prüfung der Klimawechselfestigkeit

Car Parts, Testing of Climate Cycling Resistance

DIN 50 017,Klimate und ihre technische Anwendung; Kondenswasser – Prüfklimate

Climates and their Technical Applicatio; Condensed Water – Testing Climates DIN 50 021,Sprühnebelprüfungen mit verschiedenen Natriumchlorid – L?sungen

Inspection with Sprayed Mist of Different Sodium Chloride – Solutions

DIN 50 960-1,Galvanische überzüge; Bezeichung in technischen Dokumenten

Plated Layers; Labelling in Technical Documentation

DIN EN 1403,Korrosionsschutz von Metallen; Galvanische überzüge

Corrosion Protection of Metals; Plated Coatings

DIN EN 1464,Klebstoffe – Bestimmung des Sch?lwiderstandes von hochfesten Klebungen –

Rollensch?lversuch

Adhesives – Determination of the Tear Resistance of High Performance Splices –

Reel Tearing Test

DIN EN 12540,Korrosionsschutz von Metallen; Galvanische Nickel-überzüge und Nickel-Chrom-überzüge, Kupfer-Nickel-überzüge und Kupfer-Nickel-Chrom-überzüge (outline)Corrosion Protection of Metals; Plated Coatings of Nickel and Nickel Chromium,

Copper – Nickel - Coatings and Copper – Nickel – Chromium Coatings.

DIN EN ISO 1463,Metall- und Oxidschichten; Schichtdickenmessung; Mikroskopisches Verfahren

Metal- and Oxide Layers; Determination of Thicknesses; Microscopic Methods DIN EN ISO 2177,Metallische überzüge; Schichtdickenmessung; Coulometrisches Verfahren durch anodisches Abl?sen

Metallic coatings; Determination of Thicknesses; Coulometric Method by Anodic

Dissolution

DIN EN ISO 2409,Gitterschnittprüfung

Cross Hatch Testing