GCr15轴套纵扭超声磨削表面形貌预测及试验研究  

Prediction and Experiment on Surface Morphology of Longitudinaltorsional Ultrasonic Grinding of GCr15 Shaft Sleeve

作　　者：楚帅震 牛赢[1] 王壮飞 焦锋[1] CHU Shuai-zhen;NIU Ying;WANG Zhuang-fei;JIAO Feng(School of Mechanical and Power Engineering,Henan Polytechnic University,Henan Jiaozuo 454003,China)

机构地区：[1]河南理工大学机械与动力工程学院,河南焦作454003

出　　处：《表面技术》2023年第9期294-305,339,共13页Surface Technology

基　　金：国家自然科学基金(52175399);河南省重点研发与推广专项(232102221015);河南省高校基本科研业务费专项资金(NSFRF200102)。

摘　　要：目的构建纵扭超声磨削(LTUG)表面形貌预测模型,分析工艺条件和参数对表面粗糙度Ra值的影响,揭示GCr15轴套LTUG内圆表面形成机理。方法基于弹性变形对LTUG单颗磨粒运动轨迹的影响,根据切削厚度概率密度函数和相邻磨粒轨迹重叠效应,建立了多磨粒超声振动作用下的最大未变形切削厚度模型,利用表面残余材料高度公式建立了GCr15轴套内圆磨削形貌预测模型,以LTUG和普通磨削(OG)方式对GCr15轴套内圆进行试验,采用正交试验验证表面形貌模型的准确性,观察并分析LTUG和OG作用后的GCr15轴套内圆表面形貌,最后利用所建立的表面形貌模型,研究磨削参数和超声振幅对表面Ra值的影响。结果结果表明,基于所建立的表面形貌模型计算而得的表面Ra值与试验结果间的误差在13.2%以内,与OG相比,LTUG作用下的表面沟槽磨痕更均匀;LTUG作用下的表面轮廓呈现规律的周期性波动,且随振幅的增大,表面轮廓顶峰之间的间距逐渐增大;LTUG作用下的表面Ra值均低于OG,表面Ra值的降低幅度最大达到20%,随振动幅值的增大,表面Ra值逐渐减小,当振幅增大到一定程度时,表面Ra值呈现增大趋势。结论建立的LTUG形貌预测模型具有良好的准确性,在合适的工艺参数下,LTUG可明显降低表面Ra值,与OG相比,在相同时间内,LTUG作用下的磨粒运动轨迹长度更长,且LTUG区域的弹性变形对磨粒运动轨迹和最大未变形切削厚度均有不同程度的影响。In order to establish a surface morphology model of longitudinal-torsional ultrasonic grinding(LTUG),analyze the effect of process conditions and parameters on surface roughness Ra value,and reveal the formation mechanism of internal surface of GCr15 shaft sleeve during LTUG.Firstly,a motion trajectory model of a single abrasive grain in LTUG was established.Combined with the number of vibrations of the abrasive grains in the grinding time,the grinding arc length of a single abrasive grain in the grinding area was obtained.Then,based on the effect of elastic deformation between the grinding wheel grain and the workpiece on the movement track of a single abrasive grain in longitudinal-torsional ultrasonic grinding,according to the probability density function of cutting thickness,the maximum undeformed cutting thickness model of a single abrasive grain under longitudinal torsional ultrasonic vibration was established.Considering the overlapping effect of adjacent abrasive grain motion tracks,the maximum undeformed cutting thickness model under the action of multiple abrasive grains was established.Finally,a morphology prediction model of GCr15 shaft sleeve internal grinding was established using the surface residual material height.The reliability of the morphology model was verified by orthogonal tests of four factors and three levels.Several groups of tests were conducted on the inner ring of GCr15 shaft sleeve by LTUG and ordinary grinding(OG).The surface Ra value of GCr15 shaft sleeve under different grinding methods was observed and analyzed with a field microscope of super depth.The grinding surface Ra value under different amplitudes was simulated and its contour lines were extracted based on established surface morphology model.The actual surface Ra value was observed with a confocal microscope and its contour lines were extracted.The grinding simulation contour and the actual contour were compared and analyzed.The effect of process parameters on the surface Ra value was investigated using the single-facto

关 键 词：GCr15轴套 弹性变形 纵扭超声磨削 表面形貌模型 表面粗糙度 

分 类 号：TG580[金属学及工艺—金属切削加工及机床]