(湖南大学 机械与汽车工程学院 汽车车身先进设计制造国家重点实验室，长沙 410082)
摘 要: 建立Al2O3热压陶瓷激光辅助切削准稳态传热模型，采用有限差分方法，利用MATLAB软件，结合材料的受热软化特性，计算得到工件的温度场分布，并由此确定不同激光参数(激光功率、光束移动速度和光斑半径)下的切削深度。模拟计算发现工件表面等温线为卵圆形，横截面呈抛物线型，纵截面呈对称分布形式，而计算确定工件横、纵截面1 000 K等温线所对应的深度值为加工时合适的切削深度；通过对比分析发现：不同参数下温度场计算确定的切削深度值与实验值较吻合，采用较高的激光功率、较低的激光移动速度和工件表面受辐照激光光斑半径有利于切削区域材料的充分软化，从而获得较大的切削深度。
关键字: Al2O3热压陶瓷；激光辅助切削；温度场；切削深度
（College of Mechanical and Automobile Engineering, State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha 410082, China）
Abstract:A quasi-steady heat conduction model for laser-assisted machining hot-sintered Al2O3 ceramics was established. Based on finite difference method(FDM), temperature field distribution of the workpiece was calculated by means of MATLAB. Considering the softened characteristic of material after being heated, cutting depths under different laser parameters (laser power, beam moving speed and spot radius) were obtained. The simulation results indicate that the isotherms are ovoid on the surface, parabolic in cross-section and symmetrical in longitudinal section. The corresponding softened depth to isotherm of 1 000 K is concerned as the proper cutting depth. The calculated cutting depths are in good agreement with the experimental ones under different parameters. The results show that the cutting depth and material removal rate can be increased by increasing the laser power, decreasing the beam spot radius and reducing the moving speed of laser beam.
Key words: hot-sintered Al2O3 ceramics; laser-assisted machining; temperature field; cutting depth
