激光焊接铸钛和锻钛疲劳强度的研究

目的：测试激光焊接铸造和锻造纯钛（TA2）及钛合金（TC4）疲劳强度和拉伸负荷,探讨一定条件下激光焊接后铸造和锻造钛试件的疲劳强度及临床应用的可行性。方法：将铸造和锻造纯钛及钛合金加工成一定规格的试件,进行激光焊接,焊后用疲劳试验机测得母材及焊件的疲劳强度,并进行断裂试件断口的扫描电镜分析,结果分别进行比较。结果：激光焊接铸造和锻造纯钛及钛合金试件的疲劳强度与对照组有统计学差异,激光焊接断口有气泡及断裂裂纹。结论：与母材相比,激光焊接铸造和锻造纯钛及钛合金试件的疲劳强度有统计学差异。

Comparison of fatigue strength of laser-welded wrought and cast titanium

Objective: This study evaluated the fatigue strength of laser-welded wrought and cast titanium specimens fabricated from commercial pure titinium (TA2) and titanium alloy (TC4). Methods: TA2 and TC4 were milled or cast into a certain size and joined with laser welding. A fatigue testing machine was used to test tensile load and fatigue strength. The fatigue fracture surface was examined by scanning electron microscopy (SEM). Results: The rusults showed that the laser-welding decreased the fatigue strength of wrougth and cast titanium test specimen considerably compared to inact specimens. Fatigue strength of the original cast titanium made no difference from that of the wrought titanium. SEM examination showed that there were defects such as pore and cracks in the welding zone. Conclusion: The fatigue strength of the laser-welded wrought and cast titanium or titanium alloy were slightly lower than those of intact specimens