钛合金的已加工表面残余应力的数值模拟

为了揭示高速切削对航空钛合金加工表面残余应力的影响，利用三维斜角切削有限元模型对钛合金Ti6Al4V的高速切削加工过程进行了模拟，获得了不同切削速度和不同切削深度下的已加工表面残余应力分布.模拟结果表明：切削速度对已加工表面残余应力具有重要影响，而切削深度对已加工表面残余应力影响较小; 已加工表面层残余应力为拉应力，沿深度方向由拉应力逐渐过渡到压应力; 3个主方向的残余应力值随切削速度的增加而增加，而随切削深度的增加无明显变化; 切削速度和切削深度对残余应力层的厚度影响都很小.

Numerical simulation on surface residual stress for titanium alloy

To reveal the influence of high speed cutting on the residual stress of Ti6Al4V, the cutting process was simulated using the 3D oblique cutting finite element model at different cutting speeds and cutting depths.The distribution of surface residual stress was achieved.The results showed that the cutting speed has great influence on the surface residual stress,while the cutting depth has little influence on the residual stress.The surface residual stress of workpiece is tensile stress.Along the depth direction,the tensile stress is transformed to the compressive stress.The three principal stresses increase with the increasing of the cutting speed,but has no obvious change with the increasing of cutting depth.Both the cutting speed and cutting depth have little influence on the thickness of the residual stress layer.