【摘要】 为了研究高速切削加工过程中的温度场分布情况,根据金属切削平面应变原理及温度场的有限元理论,通过对材料本构模型、刀-屑接触摩擦等关键物理环节建模,建立了正交切削有限元模型。采用伴随刀具行程移动的网格窗口描述切削区的局部大变形,使用摩擦窗口表述刀/屑间的摩擦关系,设定合适的热边界条件和形变边界条件对高速切削AISI-1045钢的温度场进行数值模拟。研究表明,最高温度集中在刀/屑接触面上刀尖附近的局部区域;刀具最高温度点位于前刀面上距刀尖不远处;工件内部温度几乎不变,仅表面的薄层发生温度变化;切削速度对切削温度影响很大,高速时温升变缓;切削厚度对切削温度影响较小。更多还原

【Abstract】 A finite element model of orthogonal cutting was constructed in order to study the temperature field in high speed machining(HSM), followed by the plane strain principle in metal cutting and finite element theory for temperature field.Several key techniques such as material constitutive relations and tool-chip interface friction were modeled.To improve the simulating accuracy, mesh windows and friction windows were applied to implement the local large deformation and the tool-chip friction simulation respectively, and the thermal and deformation boundary conditions were properly set.Then, the temperature field in HSM of carbon steel AISI-1045 was digitally simulated.The results show that the top temperature is localized in the tool tip not far away from the rake edge, only the temperature of the workpiece surface changes and the influence of the cutting speed on the temperature is more important than that of the undeformed chip.更多还原