Combining Spark Plasma Sintering with laser cladding: A new strategy for fabricating microstructure of defect-free and highly wear-resistant AlCoCrFeNi high-entropy alloy

Abstract

This study investigates the advantages of combining Spark Plasma Sintering (SPS) with Laser Cladding (LC) technology in the production of AlCoCrFeNi high-entropy alloy (HEA). By comprehensively applying SPS and LC composite processing techniques, we achieve rapid preparation of high-performance AlCoCrFeNi HEA. SPS technology enables rapid sintering under high-temperature conditions, while LC technology allows precise control of microstructure generation on the workpiece surface. Experimental results show that AlCoCrFeNi HEA prepared by single SPS technology exhibits a body-centered cubic (BCC) solid solution structure, while AlCoCrFeNi HEA processed with a combination of SPS and LC techniques demonstrates a complex microstructure consisting of equiaxed BCC phase, uniformly distributed granular face-centered cubic (FCC) solid solution, and α-Al2O3 ceramic phase. Composite processing also eliminates voids and pores caused by single SPS processing, resulting in AlCoCrFeNi HEA with low porosity. Furthermore, the maximum hardness of AlCoCrFeNi HEA produced by composite processing technology is approximately 644.1HV, significantly higher than that of AlCoCrFeNi HEA processed solely by SPS (approximately 328.7HV). Wear test results show that AlCoCrFeNi HEA processed by composite machining exhibits significant advantages in wear resistance, with the width and depth of wear tracks significantly reduced compared to AlCoCrFeNi HEA processed solely by SPS technology, with a 33.17% higher wear rate. In conclusion, composite processing using SPS combined with LC technology enables rapid preparation of AlCoCrFeNi HEA with low porosity, high hardness, and high wear resistance.

Keywords

• High-entropy alloy
• Laser cladding
• Spark plasma sintering
• Microstructure
• Wear test