The effect of substrate bias voltage on the adhesion strength of ta-C coated tools prepare by filtered cathode vacuum arc

Abstract

ta-C coating have found application for cutting tools. In this study, the effect of bias voltage on the physical properties of the coating and cutting performance were experimentally investigated. A bias voltages were applied with 0, 75, 150, 300 V and thicknesses were 430 nm. The results showed that the regardless of the bias voltage, the adhesion strength indicates that all ta-C coatings were HF 1. However, increasing bias voltage will increase the C = C boning at the coating, especially 150 and 300 V. Moreover, hardness values also decreased with increased bias voltage. For the cutting test, the ta-C coating from the lowest I(D)/I(G) value (0.5) with 75 V is selected. After cutting test, the adhesive of Al debris and delamination on the ta-C coated surface was three times lower than commercial DLC. This phenomenon shows that heat resistance of ta-C coating is dominant with high portion of sp3 fraction.