Crucible 17Cr-4Ni is a version of 17CR-4Ni which has been modified to substantially improve machinability and other properties. Patented 17Cr-4Ni Super-X meets industry specifications for 17Cr-4Ni. The machinability improvement, of up to 45% over conventional solution-treated ( Condition A) 17Cr-4Ni material, has been achieved by close control of the chemical composition within the standard range. Crucible 17Cr-4Ni shows a significant improvement in ductility in all conditions, especially the solution-treated condition. In addition, the steel is markedly tougher than conventional 17Cr-4Ni as measured by Charpy impact tests. Crucible 17Cr-4Ni Super-X is a precipitation-hardening stainless steel which is capable of a high strength and hardness levels after a relatively simple heat-treatment procedure. This grade is martensitic and magnetic in both the solution-treated and precipitation-hardened conditions. It has high resistance to crack propagation, good transverse properties, and corrosion resistance is normally superior to the regular martensitic chromium-type of stainless steel. Because of the single low-temperature (900-1150°F) precipitation-hardening heat treatment of this grade, scaling and distortion are virtually eliminated. This enables materials to be finish machined to close tolerance prior to heat treatment. Information provided by Crucible Specialty Metals. |