Böhler (or Boehler) K890 Microclean is a cold-work tool steel that is highly ductile, but with a high fatigue strength. This datasheet provides information on composition, physical properties, and elasticity as well as fracture toughness. It also includes information on wear resistance as well as heat treating and powder metal forms. Filing Code: TS-664. Producer or source: Böhler-Uddeholm North America.