梯度基体负偏压真空多弧离子镀沉积TiN涂层及其力学性能

目的通过梯度基体负偏压沉积工艺,获得综合性能优良的Ti N涂层。方法采用多弧离子镀工艺,在0~-180 V连续变化的梯度基体负偏压参数下沉积梯度Ti N涂层。通过X射线衍射仪和扫描电子显微镜对涂层的物相结构和形貌进行分析,通过纳米压痕和纳米划痕对涂层的力学性能进行系统研究。结果与无梯度沉积的涂层相比,梯度基体负偏压沉积Ti N涂层的(111)晶面衍射峰减小,厚度增加,表明涂层的沉积速率增大。经测试,梯度涂层的断裂临界载荷L_(c2)=215.21 m N,硬度值H=31.2GPa,弹性模量E=498 GPa,塑性变形临界载荷L_y=81.65 m N;无梯度沉积涂层的L_(c2)=248.63 m N,H=29.6 GPa,E=452 GPa,L_y=23.39 m N。二者相比之下,梯度涂层虽然断裂临界载荷有所减小,但硬度值和弹性模量均有所增大,并且塑性增大,塑性变形临界载荷大幅增加,综合力学性能提高。结论梯度基体负偏压沉积工艺改变了常规的单一参数设置,在沉积过程中,基体负偏压对涂层生长的影响不断改变,获得的涂层具有结构上的梯度变化,从而力学性能得到了改善。

Arc Ion Plating with Gradient Bias Voltage Deposition and Mechanical Properties of TiN Coatings

Objective To obtain TiN coatings with excellent comprehensive performance through gradient bias voltage deposition. Methods Gradient TiN coatings were deposited by arc ion plating with gradient bias voltage through 0 V to -180 V. Coating phase structure and morphology were analyzed through X-ray diffraction and scanning electron microscope. The mechanical properties were investigated through nanoindentation and nano-scratch test. Results Compared with the constant bias voltage coatings, the intensity of the (111) peak decreased in the gradient bias voltage coatings. The thickness of the coatings decreased, which indicated that the deposition rate was increased. The testing results showed as below. The gradient bias voltage coatings had the Lc2 of 215. 21 mN, the hardness of 31. 2 GPa, the elastic modulus of 498 GPa and the Ly of 81. 65 mN. The constant bias voltage coatings had the Lc2 of 248. 63 mN, the hardness of 29. 6 GPa, the elastic modulus of 452 GPa and the Ly of 23. 39 mN. Even though the Lc2 of the gradient bias voltage coatings decreased, the hardness, the elastic modulus and the plasticity increased, and the (Ly) increased greatly. A TiN coating with excellent comprehensive performance was achieved. Conclusion The gradient bias voltage deposition method was used to change the single parameter setting. The gradient bias voltage changed the influence of the coating growth continually during deposition, which made the obtained coatings have a gradient change in the structure. Thus, the mechanical properties were improved.