CTS-204P is a steel made by Carpenter Steel and consists of:
Some information from Carpenter's website:
Carpenter CTS 204P alloy is a highly wear and corrosion resistant, air hardening martensitic cold-work stainless die steel produced using Carpenter's Mirco-Melt powder metallurgy (P/M) process. The excellent wear resistance of the alloy is provided by a significant volume fraction of hard vanadium-rich carbides, while the alloy's outstanding corrosion resistance is obtained as a result of the chromium-rich matrix. The application of Carpenter's Micro-Melt P/M processing creates a segregation-free and homogenously fine carbide and grain size distribution, and when coupled with the use of molten metal filtration, results in improved cleanliness and toughness compared to conventionally cast and wrought processed material. CTS 204P alloy's uniform microstructure, fine carbide distribution, cleanliness and high chromium content, is responsible for the material's excellent combination of wear resistance, toughness, polishability and corrosion resistance.
CTS-204P came about as a "micro-melt" (second generation PM) version of Latrobe's Duratech 20CV (Carpenter was also smelting 20CV for Latrobe with a first-generation processes); Böhler Uddeholm's M390 is basically identical in composition, with BM's own PM process. (More comparison details at Alpha Knife Supply )