Structure and Oxidation Resistance of Mo-Y-Zr-Si-B Coatings Deposited by DCMS and HIPIMS Methods Using Mosaic Targets

Abstract

In this study, Mo-(Y,Zr)-Si-B coatings were obtained by direct current magnetron sputtering (DCMS) and high-power impulse magnetron sputtering (HIPIMS) using mosaic targets. The results showed that the addition of Y and Zr into the composition of Mo-Si-B coatings led to the suppression of columnar grain growth, a decrease in the crystallite size of h-MoSi2 phase from ~50 to ~5 nm, and an increase in the amorphous to crystalline phases ratio Doping of the Mo-Si-B coating with Y and Zr promoted an increase in oxidation resistance at a temperature of 1000 °C. The introduction of yttrium into the composition of Mo-Si-B contributed to an increase in their crack resistance when heated to 1300 °C. High oxidation resistance of the coatings was provided by a defect-free SiO2 + MoO3 + Y2O3 surface layer. The transition from the DCMS mode to HIPIMS decreased the texture of the Mo-Si-B coatings. The use of an HIPIMS mode led to a decrease in the oxidation rate of Mo-(Y)-Si-B coatings at T = 1000 °C by 1.6–4.5 times compared to DCMS. In the case of Mo-Y-Si-B coatings, the use of HIPIMS led to a decrease of more than 50% in the thickness of the oxide layer at a temperature of 1300 °C.

Keywords

• direct current magnetron sputtering
• high-power impulse magnetron sputtering
• MoSi₂-based coating
• yttrium
• structure
• oxidation resistance