机械零件的疲劳和断裂近几年来造成航空、航天、汽车、造船、桥梁等各个领域引发工程事故,给社会带来了重大的人员伤亡和经济损失。因此,研究材料的强度和寿命尤为重要。通过316L不锈钢高速旋转丝刷表面纳米化,使材料表面出现一层致密的纳米层,从而整体提高了材料的力学性能,提高材料的强度和寿命。通过扫描电镜比较材料纳米化前和纳米化后的断口形貌,分析其起源区、扩展区、瞬断区的区别和影响材料疲劳寿命的因素。实验结果表明材料表面纳米化能提高材料的强度、寿命。纳米层越均匀、越厚材料的强度越高、寿命越长。 Fatigue and fracture of mechanical parts have caused engineering accidents in various fields such as aviation, spaceflight, automobile, shipbuilding and bridges in recent years, causing heavy casualties and economic losses to the society. Therefore, the study of the strength and life of the material is particularly important. Through the surface of 316L stainless steel high-speed rotary wire brush nano-nano, so that a dense layer of nano-material appears on the surface of the material, thus improving the mechanical properties of the material as a whole to improve the strength and life of the material. Scanning electron microscopy (SEM) was used to compare the fracture morphology before and after the nanomaterials. The differences of the origins, extensions and momentary regions and the factors affecting the fatigue life of the materials were analyzed. The experimental results show that nanocrystallization of materials can improve the strength and life expectancy of materials. Nano layer more uniform, thicker the higher the strength of the material, the longer life expectancy.