中文摘要：

在常温和低温下对砷化镓单晶进行压痕实验,分析温度对砷化镓单晶片显微硬度及其裂纹产生和扩展的影响。结果表明：当试验载荷处在低于0.244N的小载荷区时,砷化镓单晶片的显微硬度随着载荷的增加而增大;当载荷处在大于0.244N的高载荷区时,砷化镓单晶片的显微硬度则随载荷的增加而减小。同一载荷下,随着温度的升高,压痕过程中所产生的裂纹长度逐渐增长。在不同温度下,随着载荷的增加,砷化镓单晶片经历了从塑性变形到脆性断裂的转变。减小载荷和降低加工区温度,有利于减少或防止裂纹的产生,使砷化镓的加工处于塑性模态,从而有利于提高加工精度。

英文摘要：

Indentation experiments on gallium arsenide （GaAs） single crystal were carried out at room and low temperature. The effects of temperature on the micro-hardness, crack initiation and expansion of GaAs single crystal were analyzed. The results show that when the test load was in a small zone less than 0.244 N, the micro-hardness of GaAs increases with the increase of load; when the load was larger than 0.244 N, the micro-hardness decreases with the increase of load. Under the same load, the crack length of GaAs increases with the increase of temperature. At different temperatures, the indentation of GaAs single crystal changes from plastic deformation to brittle fracture with the increase of load. The decrease of load and temperature in the processing region helps to reduce and prevent the crack generation, and also make it possible that the hard and brittle materials such as single-crystal GaAs are processed under the plastic mode, which finally can improve the precise processing.