GMNA GM512M PDF

This standard covers material and performance requirements applicable to metric neutral hardened thread forming and thread cutting screws and screw/washer assemblies intended for plastic or soft metals applications.

The primary objective of this specification is to insure that screws form or cut mating threads in materials of construction into which they are normally driven. Without deforming their own thread and without breaking during assembly or service. The types of materials of construction that are tapped with these screws are generally limited to plastic or soft nonferrous metals (aluminum/zinc die-cast, copper, brass) of hardness HRB 70 max.