Novel microstructure and properties of multicomponent CoCrCuFeNiTix alloys

CoCrCuFeNiTix (x values in molar ratio, x = 0, 0.5, 0.8 and 1.0) were prepared by arc melting of the pure elements and suction casting under an argon atmosphere. Both CoCrCuFeNi and CoCrCuFeNiTi0.5 alloys form a single FCC solid solution. While the alloys of CoCrCuFeNiTi0.8 and CoCrCuFeNiTi are basically composed of primary FCC solid solution and eutectic mixture of FCC phase and Laves phase of Fe2Ti type. The yield strength of the alloys increases from 230 MPa to 1272 MPa with the increase of Ti addition, among which the CoCrCuFeNiTi0.5 alloy, especially, exhibits compressive strength of up to 1650 MPa together with extensive work hardening and large plastic strain limit of 22%. An interesting transition from paramagnetism to superparamagnetism has been discovered due to the appearance of nanoparticles embedded in the amorphous phase.