Study on microstructure and properties of Cr2AlC/Ni5Al composite coating
ZHANG Weiping1,2,ZHANG Penglin1,2,NIU Xianming1,2
(1. College of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China;
2. State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals, Lanzhou University of Tech‐
nology, Lanzhou 730050, China)
Abstract:Pure Cr
2AlC (MAX phase) powder was prepared by pressureless sintering, and then used as the rein‐
forcing phase of Ni5Al powder material. Atmospheric plasma spraying (APS) was used to prepare Cr2AlC/Ni5Al
self-lubricating composite coatings with different Cr2AlC content. The microstructure and properties of the coat‐
ings were analyzed, and the friction properties of the composite coatings were focused on. The results show that
the coating is dense as a whole, and the components exhibit good wettability. Cr2AlC significantly improves the
hardness of the composite coating. The 10%Cr2AlC-Ni5Al composite coating has the lowest friction coefficient
and wear rate, 0.45 and 1.82×10-5 mm3/(N·m) respectively. The surface cracks of the coating are significantly re‐
duced, and the self-healing properties of Al2O3 protect the coating. As the content of Cr2AlC increases, the porosi‐
ty of the coating increases and the tribological properties of the composite coating decrease.