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为研究Cu/Zr纳米多层膜的力学性能及塑性变形行为,采用磁控溅射方法制备了调制比为1,调制周期Λ=12,20,40 nm的Cu/Zr纳米多层膜,利用X射线衍射(X-Ray Diffraction,XRD)和扫描电子显微镜(Scanning Electron Microscopy,SEM)对纳米多层膜的晶体结构和截面形貌进行了表征,利用纳米压痕仪在0.01、0.03、0.05、0.1、0.2、0.5s-1等应变率下采用连续刚度法测量了多层膜的硬度。结果表明:不同调制周期结构的Cu/Zr纳米多层膜结晶性良好;Λ=12,20,40 nm的Cu/Zr纳米多层膜的强度(H/2.7)分别为1.90、1.83、0.80 GPa,Cu/Zr纳米多层膜的强度随调制周期的减小而增大,其塑性变形机制在调制周期减小到20 nm后由位错单层滑移机制转变为位错穿越界面运动机制;Λ=12,20,40 nm的Cu/Zr纳米多层膜的应变率敏感指数m分别为0.042、0.033、0.025,Cu/Zr纳米多层膜的应变率敏感指数随调制周期的减小而增大,这可能是由调制周期减小导致的晶粒尺寸减小和非共格界面密度的增大引起的。
In order to study the mechanical properties and plastic deformation behavior of Cu / Zr nano-multilayers, a Cu / Zr nano-multilayer with a modulation ratio of 1 and a modulation period of Λ = 12, 20 and 40 nm was prepared by magnetron sputtering. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the crystal structure and cross-sectional morphology of the nano-multilayers. The nanoindentation was carried out at 0.01,0.03,0.05, 0.1, 0.2, 0.5s-1 and other strain rates were measured by continuous stiffness multi-layer film hardness. The results show that the Cu / Zr nanocomposite films with different modulation period have good crystallinity. The strength (H / 2.7) of Cu / Zr nanosheets with Λ = 12, 20 and 40 nm are 1.90, 1.83 and 0.80 GPa, respectively , The strength of Cu / Zr nano-multilayer increases with the decrease of the modulation period, and the plastic deformation mechanism shifts from dislocation monolayer slip mechanism to dislocation crossing interface movement after the modulation period decreases to 20 nm. The strain rate sensitivity index (m) of Cu / Zr nano-multilayers with Λ = 12, 20 and 40 nm were 0.042, 0.033 and 0.025, respectively. The strain rate sensitive index of Cu / Zr nano- This may be caused by the decrease of the grain size and the increase of the density of non-coherent interface caused by the decrease of the modulation period.