机器人谐波减速机柔性轴承用钢的超高旋转弯曲疲劳强度的研究  

Research on Ultra-high Rotary Bending Fatigue Strength of Flexible Bearing Steels for Robot Harmonic Speed Reducer

作　　者：刘烨 桂煜琳 尹青 吴小林 缪新德 Liu Ye;Gui Yulin;Yin Qing;Wu Xiaolin;Miao Xinde(R&D Institute,Jiangyin Xingcheng Special Steel Works Co.,Ltd.,Jiangyin 214429,China)

机构地区：[1]江阴兴澄特种钢铁有限公司研究院,江阴214429

出　　处：《特殊钢》2024年第3期105-113,共9页Special Steel

摘　　要：采用电弧炉生产工艺,控制废钢/铁水比为80%以上,开发出长寿命机器人谐波减速机柔性轴承用钢,从非金属夹杂物、奥氏体晶粒度、碳化物带状组织方面对比柔性轴承用和传统滚动轴承用钢的冶金质量,并利用旋转弯曲疲劳试验的方法测试柔性轴承用和传统滚动轴承用钢在107循环周次条件下的疲劳强度。机器人谐波减速机柔性轴承用钢的w[O]<0.0004%,w[Ti]<0.001%,A类硫化物类非金属夹杂物≤1.0级,B类和D类氧化物类非金属夹杂物≤0.5级,极值统计法预测最大球状夹杂物的尺寸<30μm,检验结果表明柔性轴承用钢具备超高纯净度。通过在冶炼过程增加Al和N的元素含量,柔性轴承用钢具有10级的奥氏体晶粒度,远高于传统滚动轴承用钢的8.5级晶粒度。通过延长高温扩散时间,7.1和7.2级别的碳化物带状组织占比要高于传统滚动轴承用钢,超高晶粒度和碳化物带状组织的带宽减小表明柔性轴承用钢具备超高组织均匀性。柔性轴承用钢在107循环周次条件下具有超高旋转弯曲疲劳强度为1016 MPa,疲劳寿命略高于传统滚动轴承用钢。The flexible bearing steel with long fatigue life using for robot harmonic speed reducer has been successfully developed by applying EAF process technology.The ratio of scrap to hot metal was controlled more than 80%.This paper compared the metallurgical quality of flexible bearings and traditional rolling bearings in terms of non-metallic inclusions,austenite grain size and carbide banding structure,the fatigue strength of steel used for flexible bearing and traditional rolling bearing under 107 cycles was tested by the method of rotary bending fatigue test.The O content of steel used for flexible bearings of robot harmonic reducer was less than 0.0004%,the Ti content was much less than 0.001%,non-metal inclusions of class A sulfide≤1.0 grade,non-metal inclusions of class B and D oxide≤0.5 grade.The size of the maximum spherical inclusion was less than 30μm.The test results show that the flexible bearings have ultra-high purity.By increasing Al and N chemical composition in the smelting process,the austenite grain size was 10 grade in the flexible bearing steel,much higher than 8.5 grade in the traditional rolling bearing steel.The proportion of carbide banding structure of 7.1 and 7.2 grade was higher than that of traditional bearing steel in the means of extending the high temperature diffusion time.The ultra-high austenite grain size and the decrease of the width of carbide banding structure showed that the flexible bearing steel had an ultra-high structure uniformity.In addition,the rotary bending fatigue strength of the flexible bearing steels was 1016 MPa,its fatigue life was slightly higher than that of the traditional rolling bearing steels.

关 键 词：谐波减速机 柔性轴承 晶粒度 非金属夹杂物 旋转弯曲疲劳 超高周疲劳性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]