GMW GMW14668 PDF

Note: Nothing in this standard supercedes applicable laws and regulations.

Note: In the event of conflict between the English and domestic language, the English language shall take precedence.

Purpose/Material Description.

This standard is intended for the following applications:

Interior (Code A, C, or E).

Interior applications do not require the use of discontinuous chromium or multiple layer nickel systems. For interior applications, non-discontinuous chrome (r) is permissible.

• Type 1: Standard interior usage.

• Type 2: Applications where higher coating thicknesses are required and/or performance requirements are not met with Type 1 (e.g., inside door handles, manual shifter decor rings, or bezels, may require Type 2).

• Type 3: Small parts such as radio control knob bezels. These parts do not require full plating approval per GMW16193, but only require demonstration of plating performance per this specification at Production Part Approval Process (PPAP). Refer to Appendix B, Figure B3, for geometry limitations.

Note: If no interior type is listed on the detail drawing, Type 1 is assumed.

Exterior (Code B, D, or F).

For exterior applications, discontinuous chromium plate (microporous (mp) or microcracking (mc)), in addition to a multiple layer nickel system, shall be used.

• Type 1: Legacy type (not used for new programs/approvals).

• Type 2: Standard exterior usage.

• Type 3: High corrosion service conditions (wheel claddings and caps).

• Type 4: High corrosion calcium chloride resistant chromium (Russian mud, see 3.4.10.2). Note: Code B Type 4 is considered a legacy approval, new approvals for this Type should be Code D or Code F only.

Note: If no exterior type is listed on the detail drawing, Type 2 is assumed.

Code Definitions:

The codes indicate both whether the part is interior or exterior as well as the etching and plating chemistry used in the plating process. Regardless of chemistries used in the etching and plating process, all plated parts on the vehicle shall be free of hexavalent chrome.

• Code A (Interior) and Code B (Exterior): Plating process that uses a hexavalent chrome etching and hexavalent chrome plating.

• Code C (Interior) and Code D (Exterior): Plating process that uses a hexavalent chrome etching and trivalent chrome plating process.

• Code E (Interior) and Code F (Exterior): Plating process that uses use a hexavalent chrome free etching and trivalent chrome plating process.

Symbols.

Not applicable.

Applicability.

This type of finish shall be principally used for decorative purposes. Bright and other (e.g., satin, brushed, dark, or grained) appearances are for interior and exterior plastic applications, as defined by styling and specific appearance standards.

Remarks.

None.