不同输出电压对激光焊接钴铬合金焊件疲劳强度的影响

Effect of Different Laser Output Voltages on the Fatigue Life of Co-Cr Laser-welded Joints.

目的:探讨不同输出电压对激光焊接钴铬合金试件机械强度和疲劳强度的影响。方法:将牙科钴铬合金采用激光焊接在分别在220V、250V、280V三种输出电压下焊接成哑铃形试件(n=10),以未焊接组作为对照,在材料测试机上进行三点弯曲试验,记录试件的最大压应力值和疲劳强度,并对断口进行显微晶相分析。结果:各焊接组的最大压应力值均小于未焊接组,其中220V组最小,250V组与280V组的差别无显著性;各焊接组的疲劳强度随着输出电压的升高而升高,差异有显著性,但各焊接组的疲劳强度均远小于未焊接组。结论:在一定范围内,激光焊接的疲劳强度随输出电压的升高而增大。

Objective：To investigate the effect of different laser output voltages on the mechanical properties and the fatigue life of Co-Cr laser-welded joints.Methods：Dumbbell rods made of Co-Cr alloy were laser-welded in the output voltage of 220 V,250Vand 280 V,respectively（n=10）.The non-weld group was chosen as control group.All groups were subjected to three-point bending test on the material testing machine,the maximum compressive stress values and fatigue life of specimen were record automatically.The fracture of specimen were subjected to Microscopic phase analysis.Results：The maximum compressive stress values of laser-welded groups were smaller than the non-weld group.The smallest values was found in the 220 Vgroup,and no statistically significant difference was found between 250 Vgroup and 280 Vgroup.The fatigue life of laser-welded groups increased along with the raises of output voltage,differences were statistically significant.The fatigue life of laser-welded groups were far shorter than non-weld group.Conclusion：The fatigue life of laser-welded joints increases along with the raises of output voltages within limits.