GMW17538

Description / Abstract: This specification is a raw material and component performance specification that covers the requirements for decorative authentic trim such as real wood trim and carbon fiber trim, as well as components made of decorative authentic materials. These materials are limited to areas where low levels of ultraviolet radiation and lower interior temperatures are experienced. This is based upon current chemistry limitations. The material used shall be processed to produce components of a quality such that all requirements of this specification are met.

Material Description. These materials are multilayer constructions where the decorative layer is protected with a topcoat and manufactured to a substrate. Some parts manufactured from these materials may require an aluminum, fiberglass, thermoplastic or approved equivalent layer incorporated into the lamination or as a substrate. This may help a formed part retain its shape, act as an anchor for metal mounting studs, or aid in the prevention of warpage or splintering upon impact. The bond between these layers must remain intact in all of the tests, and each unique composite shall be tested to the part construction portions of the specification.

The finish shall be a wear and soil resistant polyester, polyurethane, acrylic, or approved equivalent. The back and non-visible edges shall be sealed in a manner that will effectively prevent moisture absorption.

Certain applications such as post applied veneers, may require the use of a pressure sensitive adhesive on the side opposite the decorative veneer. If an adhesive is required, the adhesive must be uniform across the surface to which it is applied and shall be pressure sensitive over a temperature range of 0 °C to 55 °C. To protect the adhesive and facilitate handling, the adhesive mass shall be covered with a release liner which can be readily removed when the material is to be applied. The liner must adhere to the part during shipping and storage but must separate cleanly without loosening or removing adhesive.

Solar Glass. Requirements in this specification are based upon vehicles using solar glass (GMW3136 Type 4); vehicles using other types of glass will need to adjust requirements specifically for that program.

Symbols. Decorative authentic trim materials will be identified in the GM Materials Approved Source List with construction codes. These internal codes identify the decoration by the following elements:

• Technology

• Surface

• Topcoat Chemistry

• Backing Layer

• Grade

Which will be defined by the appropriate GM Materials Engineer during initial construction approval.

Applicability. Typical applications include, but are not limited to: door trim spears, door pull accents, switch plates, console trim, instrument panel trim, integrated center stack trim, gear shift knobs, steering wheel rims, and steering wheel trim.

Remarks. New authentic trim constructions (decorative layer, surface type, topcoat and chemistry) shall be approved before the intended program Integration Vehicle Engineering Release (IVER) date. Color properties must be completed to support GM vehicle build requirements. Contact the GM Materials Engineer to identify the specific program timing requirements.

All decorative trim components or parts for validation testing, and throughout production, shall be manufactured with authentic decorative raw materials previously approved to this specification.

Substrate materials, such as injection molded plastics, shall be manufactured from GM approved materials

Any change to the material, constituent, or processing requires reapproval to this specification as well as component validation and Production Part Approval Process (PPAP). No changes to the material may be made without GM Approving Materials Engineer concurrence. It is the sole responsibility of the supplier to provide the GM Approving Materials Engineer, unsolicited, documentation of any change to the material and request reapproval