Solidification and Liquation Cracking in Welds of High Entropy CoCrFeNiCux Alloys

Ping Yu; Sindo Kou; Chun-Ming Lin

doi:10.3390/ma16165621

Solidification and Liquation Cracking in Welds of High Entropy CoCrFeNiCu_x Alloys

Materials (Basel). 2023 Aug 14;16(16):5621. doi: 10.3390/ma16165621.

Authors

Ping Yu¹, Sindo Kou¹, Chun-Ming Lin²

Affiliations

¹ Department of Materials Science and Engineering, University of Wisconsin, Madison, WI 53706, USA.
² Department of Mechanical Engineering, Minghsin University of Science and Technology, Hsinchu 30401, Taiwan.

Abstract

High entropy CoCrFeNiCu_x alloys with a Cu molar ratio of x ≈ 0, 0.5, 1, 1.5 and 2 were arc welded. Solidification cracking occurred in the fusion zones of alloys with x ≈ 0.5, 1 and 1.5. Cu-rich material was observed around cracks, increasing in quantity with increasing Cu content. Liquation cracking occurred in the partially melted zone next to the fusion zone, and it propagated into the fusion zone as solidification cracking. A recently proposed index for the susceptibility to solidification cracking was tried, i.e., |dT/d(f_S)^1/2| near (f_S)^1/2 = 1, where T is temperature and f_S the solid fraction. The index was higher in alloys with x ≈ 0.5, 1.0 and 1.5, consistent with the solidification cracking observed.

Keywords: gas-tungsten arc welding (GTAW); k high entropy alloys; liquation cracking; solidification cracking.

Grants and funding

DMR 1904503/National Science Foundation