scope:

This standard covers the requirements for ferritic nitrocarburized (FNC) gray iron brake rotors. Additional requirements or agreements shall be specified by the local business units.

Material Description. The ferritic nitrocarburized case depth and rotor pre-treatment are specified by the suffixes added to the basic specification. The first two letters will designate the pre-treatment requirement of the casting. Pre-treatment AC signifies as cast condition and SR identifies a stress relieved condition. Modified stress relief treatments are identified as code SRM. The compound zone depth is identified by a two number combination designating total case depth in microns.

The rotors shall be processed according to GMW16218-SR-10 when no pre-treatment or case depth suffixes follow the basic specification.

Symbols. Not applicable.

Typical Applications. Ferritic nitrocarburized brake rotors.

Remarks. Gray cast iron rotors shall be selected from GMW4M-IR-C Table 6 and approved by GM Engineering. The specific grade shall be identified on the engineering drawing.