Brittle Fracture Effect on Dislocation Density of Single Crystal Germanium During Turning

Single crystal germanium is widely used in many industries because of its unique properties. At present, most scholars focus on the study of germanium plastic cutting and other problems. The surface damage of brittle cutting is seldom mentioned, but single crystal germanium plastic cutting must undergo brittle fracture process. Brittle fracture leads to dislocation movement resulting in residual stress in the surface layer of single crystal germanium by dislocation, which affects the subsequent processing process. The grain size, interplanar spacing, dislocation density, surface roughness and surface morphology of single crystal germanium (111) with surface depth less than 60μm were studied, respectively, by means of X-ray diffractometer and other instruments such as proscan 2100 surface profilometer. By changing the grain integrity, there is no obvious regular change in surface roughness. The dislocation density increases first and then decreases, with the increase of grain size. The existence of dislocation will affect the properties of some finished products of single crystal germanium, and may even cause the failure of ultra-precision cutting of single crystal germanium. Therefore, it is necessary to study the formation law of single crystal germanium.