17-4 stainless steel bar, also known as UNS S17400, 17-4 PH and Grade 630, is one of the original precipitation hardened grades developed in the 50’s. Primarily comprised of 17% chromium, 4% nickel, 4% copper, with the balance being iron. There are also trace amounts of manganese, phosphorus, sulfur, silicon, columbium (or niobium) and tantalum. Stainless Steel 17-4 PH delivers an excellent combination of oxidation and corrosion resistance. Other characteristics include high strength, toughness, and quality mechanical properties at temperatures up to 600° F. Engineers and designers frequently choose Stainless Steel 17-4 PH due to its high strength and superior corrosion resistance when compared to many other stainless steels.
Stainless Steel 17-4 PH can be forged, welded and formed. Machining may be formed in the solution-annealed state, or in the final heat treat condition. Desired mechanical properties such as ductility and strength can be achieved through heating the material at various temperatures.