Abstract STENTOR tool steel shows little size change or warpage during hardening. DeCarb-Free (DFC) bars, cold finished at the mill, eliminates the need for bar bark removal. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on forming, heat treating, and machining. Filing Code: TS-100. Producer or source: Carpenter. Originally published December 1960, revised February 1990.