The heat treatment of screw machine parts is typically confined to high surface quality annealing, hardening, case hardening, and brazing applications.  Low carbon and leaded steels are typically carbonitride case hardened to produce a high hardness case on a ductile core.  Medium carbon and alloy steels are through hardened for high strength applications.  Case hardening and through hardening is performed in controlled atmosphere batch and continuous oil quench furnaces.

Carbon, alloy, stainless steel and non-ferrous screw machine parts may be bright annealed in hydrogen atmosphere continuous belt furnaces and in batch vacuum furnaces.  Heat treatable 400 series stainless steel screw machine parts may be bright hardened in the same hydrogen and vacuum furnaces.  Carbon, alloy, stainless steel, and other non-ferrous materials may be bright annealed in hydrogen atmosphere and vacuum furnaces.