闭挤式精冲直齿轮成形面的显微力学化学行为分析  

Analysis on micro mechanical and chemical behaviors of forming surface of closed-extruding fine blanking spur gear

作　　者：吕琳[1] 周杰 邓明[1] LV lin;ZHOU Jie;DENG Ming(College of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054, Chin)

机构地区：[1]重庆理工大学材料科学与工程学院

出　　处：《塑性工程学报》2018年第1期156-160,共5页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51375521)

摘　　要：直齿轮的齿廓形状复杂,其主要失效部位为齿部,通过对闭挤式精冲后的直齿轮齿部金相显微组织的观察、齿顶和齿根挤剪面附近的显微硬度分布测试,分析了闭挤式精冲直齿轮齿部的显微力学行为,同时通过极化曲线试验法研究了工件在3.5%Na Cl溶液中电化学腐蚀行为。结果表明：在靠近变形区的晶粒由于强大的三向压应力作用发生了巨大的变形,越靠近挤剪面附近的金属流线越致密,齿根的金属流线比齿顶细密。由于挤剪面附近材料变形程度很大,闭挤式精冲后的直齿轮齿部的加工硬化作用明显。齿部截面越靠近挤剪面显微硬度值越大,齿部轴向面内从塌角侧到毛刺侧,齿顶与齿根的显微硬度分布完全不同。精冲加工后直齿轮件耐蚀性能也有很大的提高。闭挤式精冲后的直齿轮的齿部有很强的耐磨性、抗疲劳强度,耐腐蚀性,直齿轮的使用寿命也得到了提高。The tooth profile of spur gear is complex and the main failure part is the tooth body. The microstructure of the spur gear tooth after closed-extruding fine blanking and the micro-hardness near the squeeze surface of addendum and dedendum were tested,the micro mechanical behavior of spur gear tooth after closed-extruding fine blanking,and the electrochemical corrosion behavior was also researched by polarization curve test in 3. 5% Na Cl solution. The results show that,the grain near the deformation zone has a severe deformation due to strong triaxial compressive stress; the nearer of material to the squeeze surface,the more dense of the metal streamline,and the metal streamline of dedendum is more dense than that of addendum. The work hardening effect is obvious because of the large deformation of the material near the squeeze surface. The micro-hardness value is larger when the tooth cross section is near the squeeze surface,and the distribution of micro-hardness is completely different from sunk angle to skin needling. The corrosion resistance of spur gear is improved greatly after fine blanking. The wear resistance,fatigue strength resistance and corrosion resistance of the spur gear are improved after closed-extruding fine blanking and the life also gets longer.

关 键 词：闭挤式精冲 直齿轮 显微力学 耐蚀性 

分 类 号：TG381[金属学及工艺—金属压力加工]