Shen Qi, Liu Zhanqiang, Hua Yang, Zhao Jinfu, Lv Woyun, Mohsan Aziz Ul Hassan
School of Mechanical Engineering, Shandong University, Jinan 250061, China.
Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE/Key National Demonstration Center for Experimental Mechanical Engineering Education, Jinan 250061, China.
Materials (Basel). 2018 Jun 14;11(6):1015. doi: 10.3390/ma11061015.
Service performance of components such as fatigue life are dramatically influenced by the machined surface and subsurface residual stresses. This paper aims at achieving a better understanding of the influence of cutting edge microgeometry on machined surface residual stresses during orthogonal dry cutting of Inconel 718. Numerical and experimental investigations have been conducted in this research. The cutting edge microgeometry factors of average cutting edge radius S¯, form-factor , and chamfer were investigated. An increasing trend for the magnitudes of both tensile and compressive residual stresses was observed by using larger S¯ or introducing a chamfer on the cutting edges. The ploughing depth has been predicted based on the stagnation zone. The increase of ploughing depth means that more material was ironed on the workpiece subsurface, which resulted in an increase in the compressive residual stress. The thermal loads were leading factors that affected the surface tensile residual stress. For the unsymmetrical honed cutting edge with = 2, the friction between tool and workpiece and tensile residual stress tended to be high, while for the unsymmetrical honed cutting edge with = 0.5, the high ploughing depth led to a higher compressive residual stress. This paper provides guidance for regulating machine-induced residual stress by edge preparation.
诸如疲劳寿命等部件的服役性能会受到加工表面和亚表面残余应力的显著影响。本文旨在更好地理解在Inconel 718的正交干切削过程中，切削刃微观几何形状对加工表面残余应力的影响。本研究进行了数值和实验研究。研究了平均切削刃半径S̅、形状因子和倒角等切削刃微观几何形状因素。通过使用更大的S̅或在切削刃上引入倒角，观察到拉伸和压缩残余应力的大小均呈增加趋势。基于停滞区预测了耕深。耕深的增加意味着更多的材料被熨压在工件亚表面，这导致压缩残余应力增加。热载荷是影响表面拉伸残余应力的主要因素。对于形状因子为2的不对称珩磨切削刃，刀具与工件之间的摩擦力和拉伸残余应力往往较高，而对于形状因子为0.5的不对称珩磨切削刃，高耕深导致更高的压缩残余应力。本文为通过刃口处理来调节加工诱导残余应力提供了指导。
