Influence of boron contents on mechanical properties and high-temperature tribological behavior in (AlCrNbTiB)N coatings

Abstract

Various boron contents of AlCrNbTiBN coatings were prepared by radiofrequency reactive magnetron cosputtering on both 304 stainless steel and 100 silicon substrates. Boron-doped AlCrNbTiN coatings resulted in a dense structure and a decrease in the grain size. As compared to boron-free coatings, the hardness of AlCrNbTiBN coatings increased from 25.8 to 31.1 GPa at a boron content of 3.3 at. %. The AlCrNbTiBN coatings exhibited favorable hardness due to the increased dense structure, defect density, grain refinement, and solid solution strengthening. The wear test at 700 °C showed that coatings without boron reveal three times the wear rate than those coatings doped with boron. In this study, the multicomponent (AlCrNbTiBN) coating demonstrated favorable mechanical and tribological properties. This implies that AlCrNbTiBN coatings might provide promising applicability in the wear-resistant field at high temperatures. Furthermore, boron-doped multicomponent nitride coating appears to enhance coating’s mechanical properties and wear resistance, indicating potential development in the near future.