TC4钛合金薄壁件低温铣削变形研究

Study on Cryogenic Milling Deformation of TC4 Titanium Alloy Thin Plate Parts

钛合金薄壁件刚性差、导热系数小,在加工过程中易产生回弹变形,直接影响其加工精度和性能。基于冰固持铣削实验和ABAQUS软件二维铣削及回弹变形有限元仿真,在温度区间[20℃,-80℃]内研究了工件温度、刀具角度和装夹方式对TC4钛合金薄壁件回弹变形的影响规律,得到不同条件下变形量、残余应力、切削力和刀具温度变化曲线。结果表明:铣削与回弹仿真可以有效预测实际加工。当工件温度从20℃降到-8℃时,TC4钛合金薄壁件的回弹变形量和残余应力分别减小了5.97%和48.61%,切削力在整个温度阶段增长了4%。当刀具角度为9°时,工件变形量最大;当刀具角度从3°增大到15°时,切削力和刀具温度分别下降了14.6%和27%。与点接触相比,面接触能够有效抑制工件变形。

Titanium alloy thin-walled parts have weak rigidity and low heat conductivity,making them vulnerable to springback deformation during machining.This directly impacts on the accuracy and efficiency of the process.The influence of workpiece temperature,tool angle,and clamping method on springback deformation in TC4 titanium alloy thin-walled parts is studied between-80℃to 20℃by ice-holding milling experiment and ABAQUS two-dimensional milling and springback deformation finite element simulation.The curves of deformation,residual stress,cutting force,and tool temperature change are obtained under various circumstances.The findings demonstrate the effectiveness of milling and springback simulations in accurately predicting machining outcomes.The rebound deformation and residual stress of the thin-walled TC4 titanium alloy dereases by 5.97%and 48.61%,respectively,when the workpiece temperature is lowered from 20℃to-8℃,while the cutting force increases by 4%throughout the temperature range.When the tool angle is adjusted from 3°to 15°,both cutting force and tool temperature decreased by 14.6%and 27%,respectively.The largest amount of workpiece deformation occurres at a tool angle of 9°.Face contact is more effective than point contact in reducing workpiece deformation.