GMW GMW18076 PDF

Material Description. This standard is intended to cover the material and performance requirements of antiflutter adhesive candidates that are used to bond automotive substrates. It is anticipated that assemblies bonded with these types of adhesives will incorporate a mechanical means of attachment (i.e., hems, fasteners, and/or welds) to facilitate fixturing prior to cure of the adhesive; generally, in the heat of the paint bake ovens, or in the case of two (2) component adhesives, the assemblies will be held in appropriate fixtures until the adhesive has attained sufficient strength for handling.

Symbols. Not applicable

Applicability. The adhesives covered by this standard are meant for use in vehicle assembly plant body shops and are pumpable; other types of adhesive bonding shall be addressed in separate specifications.

Antiflutter. Bonding of inner and outer panels to eliminate metal contacts, act as a vibration dampener and can give the assembly part stiffness. For example, inner and outer panel of hood, tailgate, door, roof bow to roof, fuel filler and wheel arch.

Remarks.

Approvals. Adhesive candidates shall not be used for GM production vehicles without full approval by GM Materials Engineering. Full approval is a two (2) step process consisting of the technical approval and additionally the production approval. Technical approval requires testing to this specification with at least one (1) GM approved production substrate as specified by the approving GM Material Engineer. Adhesives meeting these requirements shall be listed as "Approved" in the GM Approved Material Source List. Adhesives can only be used in production (Production Approval) when there is an accompanying "AAA" number, that is an approved adhesive application (AAA) number for the intended application. The "AAA": number will require testing to this specification for each unique combination of substrates plus surface treatment, etc., intended to be used in vehicle production, or as specified by the approving material engineer. The AAA number can be used as surrogate for multiple bond joint configurations or multiple assembly plant locations as determined by the approving GM Materials Engineer.

Test Data Submission. Technical approval and AAA submissions shall be submitted on the standard test data template. Contact the approving GM Materials Engineer for an electronic copy of the standard test data template for submission.

Dispense. The adhesive system must be capable of being metered, mixed and dispensed using current production equipment.

Paint Bake. Adhesives approved to this specification shall be compatible with production paint systems and cannot be adversely affected by paint oven bake schedules.