Tian Zhongwang, Xue Wei, Lou Wenzhong, Liu Min, Feng Hengzhen, Wang Xiaoxia, Li Shiteng, Wu Shaokuan
School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, China.
Xi'an Institute of Electromechanical Information Technaology, Xi'an 710065, China.
Micromachines (Basel). 2025 Jun 25;16(7):744. doi: 10.3390/mi16070744.
To examine the impact of the strain rate on the anisotropic mechanical characteristics of single-crystal silicon, nanoindentation and micro-tensile-compression tests were performed. This study analyzed the effects of varying crystal orientations at different strain rates on load-displacement behavior, elastic modulus, hardness, fracture toughness, and true stress-strain responses. The nanoindentation results showed that at room temperature, single-crystal silicon exhibited an elastic recovery rate of approximately 42%. Notably, the elastic modulus remained unaffected by strain rate variations, whereas hardness increased with higher strain rates. Fracture toughness at room temperature displayed marked anisotropy, with the <100> orientation exhibiting the lowest value at 0.691 MPa·m and the <110> orientation showing the highest one at 0.797 MPa·m. Additionally, tensile and compression experiments revealed that the fracture strength of <100>-oriented silicon increased from 117 MPa at a strain rate of 0.001 s to 550 MPa at a strain rate of 0.01 s.
为了研究应变速率对单晶硅各向异性力学特性的影响，进行了纳米压痕和微拉伸-压缩试验。本研究分析了不同应变速率下不同晶体取向对载荷-位移行为、弹性模量、硬度、断裂韧性和真应力-应变响应的影响。纳米压痕结果表明，在室温下，单晶硅的弹性回复率约为42%。值得注意的是，弹性模量不受应变速率变化的影响，而硬度随应变速率的增加而增加。室温下的断裂韧性表现出明显的各向异性，<100>取向在0.691MPa·m时显示出最低值，<110>取向在0.797MPa·m时显示出最高值。此外，拉伸和压缩实验表明，<100>取向硅的断裂强度从应变速率为0.001s时的117MPa增加到应变速率为0.01s时的550MPa。
