Alloy 17-7 PH® precipitation hardening stainless steel alloy. It is a semi-austenitic being austenitic in the annealed condition and martensitic in the hardened condition. Alloy 17-7 PH® provides high strength and hardness, excellent fatigue properties, good corrosion resistance and minimum distortion upon heat treatment. It is easily formed in the annealed condition, then hardened to high strength levels by simple heat treatments to Conditions RH 950 and TH 1050. The exceptionally high strength of Condition CH 900 offers many advantages where limited ductility and workability are permissible. In its heat treated condition, this alloy provides exceptional mechanical properties at temperatures up to 900ºF (482ºC).