Study on the microstructure and wear behaviour of AlCoCrFeNiTi/NiCrBSi composite coating by atmospheric plasma spraying

摘要

The microstructure of the as-sprayed AlCoCrFeNiTi/NiCrBSi composite coating was analyzed and the microhardness and high-temperature wear resistance were investigated. The results show that a dense coating with the adhesion strength of higher than 60 MPa was prepared. The microhardness of the coating was 727 Hv. It was found that with the increase of the wear temperature, the volume loss increased from room temperature to 500°C and decreased from 500°C to 900°C. The volume loss of the as-sprayed coating at room temperature was 21% of that of 316 stainless steel. At the wear temperature of 900°C, the volume loss of the coating was about 5% of that of 316 stainless steel. Abrasion wear was the main failure mechanism of the coatings at room temperature, 500°C, 700°C and 900°C. Adhesion wear occurred at the wear temperature of 900°C. Besides, peeling wear can be found on the worn surface of the as-sprayed coatings.