基于田口方法的Al_(2)O_(3)陶瓷激光辅助车削实验研究

Experimental study of laser-assisted machining of Al_(2)O_(3) ceramics based on Taguchi method

为研究激光加工参数对Al_(2)O_(3)陶瓷材料加工表面质量的影响,采用光纤激光器和CBN刀具对尺寸为Φ10 mm×100 mm的Al_(2)O_(3)工件进行了激光辅助车削(Laser-Assisted Machining,LAM)实验。设计4因素4水平正交实验,采用田口方法,以寻求最小表面粗糙度为指标,研究了激光功率P、主轴转速S、进给速度f和背吃刀量a_(p)对表面粗糙度和刀具磨损的影响规律。经方差分析(Analysis Of Variance,ANOVA)及各因素主效应分析,各加工参数对表面粗糙度和刀具磨损影响因素大小排序依次为:激光功率>背吃刀量>进给速度>主轴转速。选取背吃刀量为0.15~0.3 mm,进给速度为3~9 mm/min,主轴转速为350~950 r/min,激光功率为60~165 W范围内,以表面粗糙度最小为指标,得到最佳加工参数组合:背吃刀量为0.15 mm,进给速度为3 mm/min,主轴转速为550 r/min,激光功率为165 W;以刀具磨损程度最小为指标,得到最佳加工参数组合:背吃刀量为0.15 mm,进给速度为9 mm/min,主轴转速为350 r/min,激光功率为165 W。实验结果表明,在合适的加工参数范围内,增加激光功率,降低背吃刀量,可使Al_(2)O_(3)工件表面粗糙度明显减小,最佳参数组合下表面粗糙度Ra=0.795μm;增加激光功率,降低主轴转速和背吃刀量,刀具磨损程度显著下降,最佳参数组合下刀具磨损值VB=58.5μm。

In order to study the influence of laser process parameters on the surface quality of Al_(2)O_(3)ceramic materials,a laser-assisted machining experiment was conducted on an Al_(2)O_(3)workpiece of sizeΦ10 mm×100 mm using a fiber laser and a CBN tool.A4-factor,4-level orthogonal experiment was designed,using Taguchi method to seek the minimum surface roughness as the index,the influence laws of laser power(P),spindle speed(S),feed rate(f)and cutting depth(a_(p))on the surface roughness and tool wear were investigated.After ANOVA and main effect analysis of each factor,the influence of each process parameter on surface roughness and tool wear was ranked in the following order:laser power>cutting depth>feed rate>spindle speed.In the range of cutting depth 0.15~0.3 mm,feed speed 3~9 mm/min,spindle speed 350~950 r/min,laser power 60~165 W,taking the minimum surface roughness as the index,the best combinations of process parameters were obtained:cutting depth 0.15 mm,feed rate 3 mm/min,spindle speed 550 r/min and laser power 165 W.Taking minimum tool wear as the index,the best combinations of process parameters were obtained:cutting depth 0.15 mm,feed rate 9 mm/min,spindle speed 350 r/min and laser power 165 W.The experimental results show that the surface roughness of Al_(2)O_(3)workpiece can be significantly reduced by increasing the laser power and reducing the cutting depth within the appropriate parameter range,the surface roughness Ra=0.795μm;the degree of tool wear decreases significantly by increasing the laser power,reducing the spindle speed and cutting depth,under the best combination parameters,the tool wear value VB=58.5μm.