Nanosecond-laser cutting of (TiZrHfNbTa)C high-entropy ceramics

Abstract

(TiZrHfNbTa)C high-entropy ceramics have wide range of application prospects due to their excellent performance, but their hardness and brittleness make them difficult to process. In this study, novel method based on nanosecond laser was used to cut (TiZrHfNbTa)C high-entropy ceramics. Results show that laser machining is efficient strategy for high-precision machining of (TiZrHfNbTa)C high-entropy ceramics. Slit width obtained via nanosecond-laser cutting is only 26.4% of that obtained via mechanical cutting, and average roughness and maximum height difference of cut surface are 2.078 and 20.497 μm, respectively, which are smaller than those obtained through mechanical cutting (4.296 and 29.706 μm, respectively). Furthermore, removal mechanism under the action of nanosecond laser was investigated, and it was found that cut surface of (TiZrHfNbTa)C high-entropy ceramics formed thin oxide recast layer together with carbide underneath. This study provides important results for precision machining of (TiZrHfNbTa)C high-entropy ceramics.