W掺杂改性TiAlN涂层的微结构及性能研究

Study on Microstructure and Properties of W-Doped TiAlN Coatings

为详细研究W元素掺杂对TiAlN涂层的微结构及性能的影响,采用Ti_(40)Al_(60)、Ti_(38)Al_(60)W_(2)和Ti_(36)Al_(60)W_(4)三种靶材制备了Ti_(0.43)Al_(0.57)N、Ti_(0.42)Al_(0.54)W_(0.04)N和Ti_(0._(40))Al_(0.53)W_(0.07)N三种涂层,并使用能量色散X射线光谱仪(EDX)、X射线衍射仪(XRD)、扫描电镜(SEM)、纳米压痕研究W元素掺杂对TiAlN涂层的成分、微观结构、力学性能、热稳定性和抗氧化性的影响。结果表明:三种涂层均呈面心立方结构;W的掺杂对涂层的硬度无明显影响,Ti_(0.43)Al_(0.57)N、Ti_(0.42)Al_(0.54)W_(0.04)N和Ti_(0._(40))Al_(0.53)W_(0.07)N涂层的硬度分别为29.1GPa、29.6GPa和30.1GPa;W的加入提高了涂层的热稳定性,退火过程中涂层完全分解温度由Ti_(0.43)Al_(0.57)N的1200℃上升到Ti_(0._(40))Al_(0.53)W_(0.07)N的1450℃;此外,在850℃氧化10h后,Ti_(0.43)Al_(0.57)N涂层已完全氧化,而Ti_(0.42)Al_(0.54)W_(0.04)N和Ti_(0._(40))Al_(0.53)W_(0.07)N氧化层厚度分别为~0.59μm和~0.53μm。

For the purpose of investigating the effect of W doped on the microstructure and properties of TiAlN coatings in detail,Ti_(0.43)Al_(0.57)N,Ti_(0.42)Al_(0.54)W_(0.04)N and Ti_(0._(40))Al_(0.53)W_(0.07)N coatings were deposited by cathode arc evaporation using Ti_(40)Al_(60),Ti_(38)Al_(60)W_(2)and Ti_(36)Al_(60)W_(4)targets,respectively.The composition,structure,mechanical properties,thermal stability,oxidation resistance of the coatings were studied by energy-dispersive X-ray spectrometer(EDX),X-ray diffraction,scanning electron microscopy(SEM),and nanoindentation.All coatings exhibit a face-centered cubic(fcc-)structure.The doping of W has no significant effect on the hardness of the coatings,and the hardness of Ti_(0.43)Al_(0.57)N,Ti_(0.42)Al_(0.54)W_(0.04)N,Ti_(0._(40))Al_(0.53)W_(0.07)N coatings are 29.1 GPa,29.6 GPa and 30.1 GPa,respectively.The incorporation of W improves the thermal stability of the coatings.The temperature of the coating's complete decomposition in the annealing process rises from 1200 for Ti℃_(0.43)Al_(0.57)N to 1450°C for Ti_(0._(40))Al_(0.53)W_(0.07)N;moreover,after oxidizing at 850°C for 10 h,the coating of Ti_(0.43)Al_(0.57)N has been completely oxidized,and the thickness of the oxidized layers of Ti_(0.42)Al_(0.54)W_(0.04)N and Ti_(0._(40))Al_(0.53)W_(0.07)N are~0.59μm and~0.53μm.