Hou Zhaoqi, Zhang Jinyu, Zhang Peng, Wu Kai, Wang Yaqiang, Liu Gang, Zhang Guojun, Sun Jun
State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
College of Materials Science and Engineering, Xi'an University of Science and Technology, Xi'an 710049, People's Republic of China.
Nanoscale. 2021 Oct 14;13(39):16649-16661. doi: 10.1039/d1nr02089g.
Ti-based films alloyed with various Ta or Zr contents were deposited on a Si (100) substrate by magnetron sputtering. Transmission electron microscopy observations suggested that the solute Ta and Zr atoms distributed uniformly in the matrix Ti, refining the grain size. The microstructure transformed from single phase α-Ti to the coexistence of (α + β)-Ti when the Ta addition was increased to 18.2 at%. Hardness and strain rate sensitivity of the Ti-based alloyed films were evaluated by nanoindentation experiments, to show the effects of constituents and their contents. The hardness was found to change non-monotonously within the studied Ta or Zr range, which could be explained by alloying dependence of the strengthening mechanisms, including partial dislocation mechanism emanating from grain boundaries, solid solution strengthening, and solution pinning strengthening. Furthermore, a mechanistic model based on partial dislocation inhomogeneous nucleation was employed to describe the composition-dependent strain rate sensitivity of the alloyed Ti films.
通过磁控溅射在硅（100）衬底上沉积了含有不同钽或锆含量的钛基薄膜。透射电子显微镜观察表明，溶质钽和锆原子均匀分布在基体钛中，细化了晶粒尺寸。当钽的添加量增加到18.2原子百分比时，微观结构从单相α-Ti转变为（α + β）-Ti共存。通过纳米压痕实验评估了钛基合金薄膜的硬度和应变速率敏感性，以显示成分及其含量的影响。发现在研究的钽或锆范围内，硬度呈非单调变化，这可以用强化机制的合金化依赖性来解释，包括源自晶界的部分位错机制、固溶强化和溶质钉扎强化。此外，采用基于部分位错不均匀形核的机理模型来描述合金化钛薄膜的成分依赖性应变速率敏感性。
