SAE ARP 1820B:2012-04-05

This practice provides a method of evaluating microhardness and microstructure very close to the surface of a disk specimen. It is useful for process control in heat treatment of steel parts to detect nitriding and carburization as well as decarburization and excessive intergranular oxidation. It also may be valuable for other evaluations, e.g., plated coatings and other materials.