? A fine-grained, vacuum-degassed carbon steel. ? It is easily machined, has excellent weldability and responds uniformly to case hardening. ? The manganese content provides greater strength and hardness compared to many other carbon steels. ? It is often used in its natural state for such applications as backup plate, stripper plates, punch pads and machine parts. ? As a case hardened material, it is used for jigs, fixtures, cams and patterns. ? Hardening: CARBURIZING: For maximum depth of hardening, 1/21", hold in carburizing salt at 1700?F for 3 hours. ? CASE HARDENING: Hold in sodium cyanide salt bath at 1500?F for 30 minutes. ? Maximum case is .006"