基于激光加热辅助切削和超声椭圆振动切削提出了激光超声复合切削加工工艺。采用聚晶立方氮化硼(PCBN)刀具对YG10硬质合金进行了常规切削，超声椭圆振动切削，激光加热辅助切削和激光超声复合切削对比试验。检测了刀具磨损量、刀具磨损形貌、工件表面粗糙度以及工件表面形貌，并通过扫描电镜(SEM)对刀具磨损区域进行了能谱分析，同时研究了激光超声复合切削硬质合金时PCBN刀具的磨损及其对工件表面质量的影响。最后，与常规切削、超声振动切削及激光加热辅助切削进行了对比试验。结果表明: 激光超声复合切削时刀具使用寿命显著增加，加工后的工件表面粗糙度平均值分别降低了79%、60%和64%，且工件表面更加平整光滑。激光超声复合切削硬质合金时，PCBN刀具的前刀面磨损表现为平滑且均匀的月牙洼磨损，后刀面磨损表现为较窄的三角形磨损带和较浅的凹坑和划痕; 刀具的失效机理主要为黏接磨损、氧化磨损和磨粒磨损的综合作用。

A laser ultrasonically assisted machining was proposed based on laser heating assisted machining and ultrasonically elliptical vibration machining. A series of comparison experiments were conducted by conventional cutting, ultrasonically elliptical vibration cutting, laser assisted cutting and laser ultrasonically assisted cutting for YG10 cemented carbide with Polycrystalline Cubic Boron Nitride(PCBN) tools. The tool wear mechanism and its effect on surface quality of a workpiece were discussed by detecting the tool wear conditions，the surface morphology and surface roughness of the workpiece and by analyzing the energy spectrum of worn areas with a Scanning Electron Microscopy (SEM). The comparison was carried out with conventional cutting, ultrasonically elliptical vibration cutting and laser assisted cutting. The results show that the flank wear of PCBN tool obtained by laser ultrasonically assisted cutting is reduced, and the average surface roughnesses of the workpieces are reduced by almost 79%，60% and 64% respectively. Therefore, the tool life is obviously lengthened and the workpiece surface is smoother by laser ultrasonically assisted cutting. In laser ultrasonically assisted machining cemented carbide, the wear on rake face is characterized by the smooth and uniform crater, the flank face has a narrow triangular wear land, shallow pits and scratches, and PCBN tool failure mechanisms are the synergistic interaction of adhesive wear, oxidation wear and abrasive wear.