The matrix structure consists of a highly tough, age-hardenable nickel martensite. The chromium content of 13.5% provides good corrosion resistance. Finish-machining is performed in the solution-annealed, as-delivered condition. Subsequent age-hardening takes place at a relatively low temperature of 480 °C and can be conducted, for example, in a convection air furnace or an electrically heated chamber furnace. The workpiece remains extremely true-to-size and little prone to distortion due to the low age-hardening temperature.