17-4 Stainless Steel (coming from the chemical makeup 17% chromium and 4% copper or UNS 17400) is a martensitic stainless grade that can be precipitation hardened through aging/heat treatment. 17-4 stainless steel, otherwise known as SAE Type 630 is frequently used with operations demanding high tensile strength and a middling level of corrosion resistance. 17-4 PH is the most used grade of martensitic precipitation hardenable alloys. 17-4 stainless steel is regarded as the most broadly formed precipitation hardening grade. Its intense tensile strength keeps its ductility and hardness at temperatures at nearly 600°F, while still demonstrating exceptional corrosion resistance in all conditions offered by Premium Alloys. Just as all martensitic metals, 17-4 is magnetic.
17-4 stainless steel can reach large levels of hardness, durability, and strength through heat treatment. 17-4 PH resists corrosion superior to any of the basic stainless steels that can be hardened. It is resistant to industries where the steel may be exposed to petroleum and most foods. Exceptional resistance to decay at roughly 1100°F. 17-4 stainless steel PH demonstrates great machinability.
Superior hardness can be obtained from welding after heat treatment. Machining conditions differ with firmness of the element. Different levels of strength and hardness can be achieved depending on the temperature it is heat treated at. The ASTM designation is A564 and common conditions are H900, H1025, H1075, H1150, and H1150D.