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It is indispensable to explore the appropriate level of surface residual stress to enhance the wear resistance of coated tools. TiAlSiN-coated carbide tools with dissimilar surface residual compressive stresses (− 300 ~ − 600 MPa) are acquired via micro-sandblasting, which are used in the high-speed sliding friction experiments and turning experiments. The influence of residual stress on the sliding wear and cutting wear performance of TiAlSiN coated tools is investigated. The results show that with the improvement of surface residual compressive stress (absolute value), the friction coefficient and wear rate are reduced. The sliding wear resistance of the coated tool is enhanced. In addition, the cutting performance of the tool is also improved with the increase of residual compressive stress (absolute value). However, the excessive surface residual compressive stresses (absolute value) can lead to severe coating peeling, which in turn impairs the capability of wear resistance. The TiAlSiN-coated carbide tool with the stress of − 500 MPa presents the best wear resistance in the high-speed sliding wear and cutting wear process. [ABSTRACT FROM AUTHOR]

Triaxial braided composites employed as structural components need to be drilled for mechanical connections. This study is to investigate the thrust force, temperature elevation, and drilling-induced damages with varying machining parameters in the drilling of triaxial braided CFRP. A high-resolution infrared thermography was carried out to capture the temperature of the panel side surface and the drill-exit surface of CFRP. The damage characteristic of drilled hole was evaluated, and a relationship between force, temperature, and hole damage was established. The obtained results indicate that the temperature of triaxial braided CFRP was mainly transferred along the fiber direction. The temperature isothermal at the drill-exit surface developed from polygonal to roughly circular with the increase of drilling depth. The braided yarns tended to deflect, and induced poorly cut fibers due to the more heat generation with the low feed, making the matrix behaved from brittle to ductile and therefore resulting in more burrs. The increase of spindle speed could restrain the burrs. A larger thrust force with high feed will result in fiber-resin debonding and more tearing defects. The delamination occurred at the interface of fiber bundles at the outermost layer with high thrust force and cracks propagated along the yarn direction. [ABSTRACT FROM AUTHOR]