Microstructure and wear resistance of AlCoCrFeNi-WC/TiC composite coating by laser cladding

Abstract

AlCoCrFeNi has excellent mechanical properties, however, its hardness and wear resistance are insufficient for engineering applications. In order to improve the wear resistance of AlCoCrFeNi coating, WC and in-situ TiC particles were used in this work. Subsequently, the microstructure, hardness, and wear resistance were studied in detail. The results showed that the in-situ TiC particles were uniformly distributed in the whole coating, ameliorating the uneven distribution of WC particles. A sound interface was formed between the particles and the coating matrix, proving the composite coating with excellent performance in wear resistance. The phase constituents of the coating matrix were the BCC and B2 phases. And BCC phase occurred lattice distortion due to the dissolution of W atoms, resulting in the solid solution strengthening of coating matrix. Furthermore, with the increase of WC content, a needle W-rich BCC phase appeared in the coating matrix. Finally, the hardness of AlCoCrFeNi-WC/TiC coatings increased from 516.4 HV 0.3 to 808.7 HV 0.3 , and the wear resistance was increased by 14 times. The improvement in hardness can be attributed to the WC particles, in-situ TiC particles, and solid solution strengthening. We prepared the AlCoCrFeNi-WC/TiC coating by laser cladding. The hardness and wear resistance are improved significantly by the WC particles, in-situ TiC particles, and solid solution strengthening. • The AlCoCrFeNi-WC/TiC coatings are reinforced by the WC particles, in-situ TiC particles, and solid-solution strengthening. • The in-situ TiC particles were uniformly distributed in the whole coatings, which ameliorates the uneven distribution of the WC particles. • The W element enhances the lattice distortion of the BCC phase, and the coating matrix is strengthened by the solid-solution strengthening. • The average hardness is increased by 292.3 HV 0.3 , and the wear resistance is increased by 14 times.