Effects of gas pressure on microstructure and performance of (Ti, Al, Zr)N coatings produced by physical vapor deposition

Abstract

In this study, a novel quaternary (Ti, Al, Zr)N coating was successfully fabricated via multi-arc ion plating technique on the Si3N4 ceramic substrate. A series of (Ti, Al, Zr)N coatings were produced on the silicon nitride (Si3N4) cutting tools by multi-arc ion plating technique using a combination of AlTi, pure Ti, and pure Zr targets. The effects of gas pressure on microstructure, deposition rate, coating thickness, phase constitution, mechanical properties, cutting performance, and wear mechanism of (Ti, Al, Zr)N coatings were systematically investigated by using four gas pressure values: 1.5, 2.0, 2.5, and 3.0Pa during the coating preparation process. It was observed from the flank worn surface that the main wear mechanism of the (Ti, Al, Zr)N coated Si3N4 cutting tools produced at different gas pressures was adhesion wear. At 1.5 and 3.0Pa, coating spalling occurred. When the gas pressure was 2.5Pa, the wear transition zone at the flank surface was obvious, which was confirmed to be positive toward the cutting performance of the cutting tools.