Inconel 718微铣削加工表面残余应力有限元仿真

Finite Element Simulation of Surface Residual Stress in Micro-milling Inconel 718

刃口圆弧半径和每齿进给量显著影响微铣削镍基高温合金残余应力,因此进行了基于ABAQUS的Inconel 718微铣削三维仿真研究.基于J-C本构方程模拟材料应力应变关系,得到相同单元在S11和S22两个方向的残余应力值,进而研究每齿进给量对表面残余应力的影响规律.进行Inconel 718微铣削实验,通过X射线衍射法测量不同每齿进给量切削过程中工件进给和垂直进给两个方向上的残余应力.进给方向的表面残余应力实测值与仿真结果最大误差为21.1%,平均误差为8.9%;垂直进给方向的表面残余应力实测值与仿真结果最大误差为31.0%,平均误差为12.3%,验证了Inconel 718微铣削加工三维有限元仿真模型的准确性.

Rounded cutting edge radius and feed per tooth have significant influence on the residual stress in micro-milling nickel-based superalloy Inconel 718. A 3D finite element model of micro-milling Inconel 718 based on ABAQUS was built. The Johnson-Cook model was adopted to simulate the plastic behavior of workpiece material. Residual stress of the same element in the direction of S11 and S22 was obtained to study the effects of feed per tooth on surface residual stress. Micro-milling experiments of Inconel 718 by changing feed per tooth were conducted, and residual stress was measured by X-ray diffraction in both the feed direction and the vertical direction of feed. In the direction of feed, the maximum relative error between the experimental and simulation results is 21.1% and the average relative error is 8.9%. While in the vertical direction of feed, the maximum relative error between the experimental and simulation results is 31.0% and the average relative error is 12.3%. The results show the validity of the as-built 3D FEM model.