This specification details the general material performance, paint layering compatibility, and processing requirements for GM worldwide approval of zinc phosphate conversion coatings.

Material Description. Materials qualified to this standard shall meet the performance shown in Table A1, Appendix A. Any material development issues, such as chemical or performance values that fall outside specified ranges, must be discussed with the appropriate GM Materials Engineer for resolution. Material must successfully complete a production trial in a target facility prior to release for general use.

Symbols. Not applicable.

Applicability. This specification applies to zinc phosphate conversion coating materials that are intended for use on automotive vehicles and associated components. These coatings must provide a crystalline, corrosion-resistant, paint adhesion promoting surface to the substrates shown in Table 1. Additional substrates may be required by the GM Engineer facilitating the approval testing.