Carpenter Project 70+ Custom 630 is a modified version of conventional stainless steel Type 630 (17Cr-4Ni) with improved machinability. The alloy has good fabrication characteristics and can be age hardened by a single-step, low-temperature treatment. See also Carpenter Custom 630, Alloy Digest SS-258, revised December 2000, and Carpenter Project 70 Stainless Custom 630, Alloy Digest SS-732, November 1998. This datasheet provides information on composition and physical properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: SS-886. Producer or source: Carpenter Specialty Alloys.