17-4 PH Stainless Steel Bar Blanks

17-4 PH stainless steel bar blanks deliver aerospace-grade strength with stainless corrosion resistance, making them one of the most specified precipitation-hardened alloys in demanding industrial applications. The designation reflects the nominal composition of 17% chromium and 4% nickel, with critical additions of 3-5% copper and 0.15-0.45% columbium that enable the precipitation hardening mechanism. This alloy achieves tensile strengths up to 190,000 psi while maintaining corrosion resistance comparable to 304 stainless. The precipitation hardening process is what sets 17-4 PH apart from conventional stainless steels. The material ships in Condition A (solution annealed at 1,900°F), which provides moderate hardness of approximately 36 HRC and is the easiest condition to machine. After machining to near-net shape, parts are aged at temperatures between 900 and 1,150°F for one to four hours. The H900 condition produces maximum strength at 44 HRC, while H1150 offers the best combination of toughness and corrosion resistance at 33 HRC. The low aging temperatures are a significant practical advantage. Parts can be hardened in a simple air furnace without protective atmosphere, and the dimensional change during aging is typically less than 0.0005 inches per inch, allowing tight-tolerance parts to be finish-machined before hardening. Machinability in Condition A is good, comparable to 304 stainless, using carbide tooling with positive rake geometry and adequate coolant. Our 17-4 PH bar blanks are supplied in Condition A, saw-cut from certified AMS 5643 mill stock in diameters from 1/2 inch through 3 inches.