Lin Wuqing, Hu Zhongwei, Chen Yue, Zhang Yuqiang, Yu Yiqing, Xu Xipeng, Zhang Jie
Institute of Manufacturing Engineering, Huaqiao University, Xiamen 361021, China.
Institute of Mechanical Engineering and Automation, Huaqiao University, Xiamen 361021, China.
Micromachines (Basel). 2022 Apr 18;13(4):640. doi: 10.3390/mi13040640.
Single-crystal silicon carbide (SiC) is widely used because of its excellent properties. However, SiC is a typical hard and brittle material, and there are many challenges in realizing its high efficiency and high-precision machining. Grinding is the main method used to achieve the high-efficiency processing of SiC, but the contradiction between processing quality and processing efficiency is prominent. Vibration-assisted grinding is an effective method to realize high-efficiency and precision machining of SiC. To reveal the vibration-assisted grinding mechanism of SiC, the vibration-assisted nano-scratch process is studied using the molecular dynamics method, and the material removal process and damage formation mechanism in the vibration-assisted scratch are analyzed. Aiming at the three main structural crystal types, 3C-, 4H- and 6H-SiC, scratch simulations were carried out. The vibration-assisted scratch characteristics of SiC polytypes were evaluated from the perspectives of scratch force and the amorphous layer. It was found that the effects of vibration-assisted scratch on different crystal structures of SiC differ, and 3C-SiC is quite different from 4H- and 6H-SiC. Through vibration-assisted scratch simulations under different scratch conditions and vibration characteristics, the influence laws for machining parameters and vibration characteristic parameters were explored. It was found that increasing the frequency and amplitude was beneficial for improving the machining effect. This provides a basis for vibration-assisted grinding technology to be used in the high-efficiency precision machining of SiC.
单晶碳化硅（SiC）因其优异的性能而被广泛应用。然而，SiC是一种典型的硬脆材料，在实现其高效高精度加工方面存在诸多挑战。磨削是实现SiC高效加工的主要方法，但加工质量与加工效率之间的矛盾突出。振动辅助磨削是实现SiC高效精密加工的有效方法。为揭示SiC的振动辅助磨削机理，采用分子动力学方法研究了振动辅助纳米划痕过程，分析了振动辅助划痕中的材料去除过程和损伤形成机理。针对3C-、4H-和6H-SiC这三种主要的结构晶体类型进行了划痕模拟。从划痕力和非晶层的角度评估了SiC多型体的振动辅助划痕特性。发现振动辅助划痕对SiC不同晶体结构的影响不同，3C-SiC与4H-和6H-SiC有很大差异。通过在不同划痕条件和振动特性下的振动辅助划痕模拟，探索了加工参数和振动特性参数的影响规律。发现增加频率和振幅有利于提高加工效果。这为振动辅助磨削技术应用于SiC的高效精密加工提供了依据。
