Microstructure and Properties of CrFeNiAlSiCux(x=0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2) Porous High Entropy alloy Prepared by Laser Sintering

By adding non-equimolar ration Cu element into Cr, Fe, Ni, Al and Si pure powder, the mixed powder was prepared was prepared. And then, the mixed powder was pressed into blank. CrFeNiAlSiCux(x=0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2) high entropy alloys (HEAs) were prepared by laser self-propagating sintering. The phase structure, microstructure, density, porosity, hardness, wear resistance and corrosion resistance were analyzed by OM, XRD, SEM, EDS, Vickers microhardness tester, abrasive wear machine and electrochemical workstation. The results show that bcc and fcc phase coexists in the alloy. With the addition of Cu, the content of fcc phase increases, but the content of bcc phase is still more than that of fcc phase. The HEAs show typical dendrite structures accompanied by many chrysanthemum-like structures, which mainly contain Cr, Fe, Si and Ni elements, and the interdendritic structure mainly contains Cu element. CrFeNiAlSiCu0.4 alloy has the best comprehensive performance, the maximum microhardness (I-1V) is 9086 MPa, the minimum wear per unit area is 48 mg cm-2, the minimum corrosion current is 0.4100 i.t/k/cm2, and the maximum corrosion potential is 149.264 mV.

Automated summary

By adding non-equimolar ratio Cu element into Cr, Fe, Ni, Al, and Si pure powder, high entropy alloys (HEAs) were prepared with varying Cu content. The addition of Cu increased the fcc phase in the alloy, while maintaining a higher content of bcc phase. The CrFeNiAlSiCu0.4 alloy exhibited the best overall performance, with highest microhardness, lowest wear and corrosion current, and highest corrosion potential.