17-4 Stainless Steel is one of the most widely used precipitation hardening (PH) grades in the world. While soft and ductile in the annealed condition, it is capable of high properties with a single precipitation or aging treatment. 17-4 is characterized by good corrosion resistance, high hardness, toughness and strength. 17-4 Stainless Steel can be machined in the annealed condition, however condition H1150M will yield best results. Post machining solution treatment of parts will be required prior to final hardening if machining in this condition. 17-4 can be successfully welded by common fusion and resistance methods, this alloy should not be joined by oxyacetylene welding. AWS E/ER630 filler metal is recommended if required. 17-4 is commonly used in both aircraft and gas turbines, nuclear reactors, paper mills, oil fields, and chemical process components.