氧化镓单晶的磨削材料去除机理和损伤演化研究

为了探究氧化镓单晶在磨削过程中材料去除机理和亚表面损伤演化规律,通过变切深纳米划痕试验模拟单颗磨粒去除材料的过程来探究磨削过程中的材料去除机理,使用粒度分别为SD600、SD1500和SD5000的金刚石砂轮对氧化镓单晶进行磨削试验,分析磨削表面形貌和亚表面的损伤演化规律.使用扫描电子显微镜和透射电子显微镜作为主要表征手段,采用有限元法分析划痕过程中的应力分布.研究结果表明,氧化镓单晶在材料去除过程中沿不同晶向扩展的交错滑移带可能导致不规则的破碎坑,取向裂纹受到（-3-10）滑移面的严重影响. 随着砂轮粒径的减小,磨削表面形貌表现为破碎坑和取向裂纹主导的脆性表面逐渐演化为完全塑性表面.

Study on Material Removal Mechanism and Damage Evolution of Monocrystalline Gallium Oxide in Grinding Process

To investigate the material removal mechanism and the subsurface damage evolution of monocrystalline gallium oxide, a systematic study was conducted by experimental methods. Firstly, the variable-depth nano-scratching test was used to simulate the material removal process of single grit and explore the material removal mechanism in the grinding process. Subsequently, the diamond grinding wheels with mesh sizes of SD600, SD1500, and SD5000 were used to carry out the grinding tests on the monocrystalline gallium oxide and to analyze the morphology of the ground surface and the evolution of subsurface damage. Scanning electron microscope and transmission electron microscope were used as the primary means of characterization, and the stress distribution during the scratching process was analyzed with the finite element method. The results indicate that the cross-acting slip band with multi-directions may lead to irregular fracture pits, and the orientation cracks were greatly affected by the （-3-10） plane of the monocrystalline gallium oxide. The grinding experiments reveal that the ground morphology, characterized by a brittle removal surface dominated by fracture pits and orientation cracks, gradually evolved into a completely plastic removal surface with the decrease of mesh sizes.