激光斜冲击对S1100型曲轴疲劳强度的影响.pdfVIP

2 0 0 7年11月 农 业 机 械 学 报 第38卷第l1期 激光斜冲击对$1 1 00型曲轴疲劳强度的影响* 鲁金忠 孙益飞 张雷洪 郭大浩 张永康 【摘要】 激光冲击加工连杆轴颈与曲柄连接处过渡区域曲面时，激光光束不能保证与曲面上每点切线方向始 终垂直，为激光斜冲击强化。用Nd：glass激光器斜冲击强化连杆轴颈与曲柄连接处圆角区域。受冲击区域显微硬 度比未冲击区域提高了65％～75 ，残余应力提高了8O ～100 o／4，使用寿命提高了150 。激光斜冲击曲轴连杆 轴颈与曲柄处圆角，残余应力和显微硬度提高最大处为圆角中心处，而这个位置正是易产生疲劳裂纹处，而圆角边 缘处是疲劳强度非敏感区，对裂纹的产生影响不大。 关键词：曲轴 激光斜冲击 疲劳强度 中图分类号：TN249 文献标识码：A Effect of Oblique Laser Shock Processing on Fatigue Strength of$1100 Crankshaft Lu Jinzhong Sun Yifei Zhang Leihong Guo Dahao。 Zhang Yongkang (1．Jiangsu University 2．University of Science and Technology of China) Abstract When laser shocks the connecting surface which iS a circle angle area between crankshaft connecting rod and crank，it can’t make the beam vertical to the tangency direction of each point on the surface，SO it is called oblique laser shock processing．In the paper，the laser oblique shocking the connecting surface experiments were carried out via the Nd：glass laser machine at Jiangsu University．The results show that the micro—hardness of the laser shock area increases about 65％～75 0A than that of non—shock area，the residual stress increases about 80 9，6～1o0 ， and the using life increases about 1 50 ．The biggest increasing area of micro—hardness and the residual stress is the center of the circle angle，which is the area of being easy to produce the fatigue crack．The edge of the circle angle is the non—sensitivity area of the fatigue intension that can’t affect the crack producing． Key words Engine crank，Oblique laser shock，Fatigue strength 光淬火[2 ]效果明显，但淬火路径的选择、曲轴淬火 引言 后变形以及回火现象造成了副作用。文献[2～5]对 曲轴强化一般采用高频淬火工艺，但高频淬火