摘要
目的:探讨不同激光功率对钴铬合金、镍铬合金焊件机械性能的影响。方法:采用临床上最常用的的2种合金进行不同功率的激光焊接,通过测定焊件的机械强度,并进行断口扫描电镜观察、熔合区金相分析和显微硬度测试,研究激光功率与焊件强度的关系。结果:钴铬合金焊件随着激光功率的增大,最大抗拉强度增大,抗弯强度则有下降的趋势;镍铬合金4组试件的最大抗拉、抗弯强度无显著差异;微观显示随着功率的增大,裂纹和气孔有增多的趋势;熔合区的显微硬度比母材高,随着功率的增大,显微硬度增大的区域增宽。结论:合适的激光功率是取得理想激光焊接接头的关键。
PURPOSE: To investigate the effect of different irradiation power on the mechanical properties of laser-welded joints. METHODS: The standard tensile test and three-point bending test rods made from Co-Cr and Ni-Cr alloy were laser-welded with different irradiation powers. Then the tensile rods were tested for the ultimate tensile strength (UTS), and the bending rods for the ultimate bending strength (UBS). The tensile fracture surface was examined by scanning electron microscopy (SEM). Metallurgical analysis and microhardness test were also performed on polished longitudinal sectioned samples. RESULTS: For Co-Cr alloy, greater irradiation power resulted in greater UTS, minor UBS. For Ni-Cr alloy, there was no significant difference of UTS and UBS between the four groups. SEM and metallurgical examination showed that the welded zone exhibited more gas pores and cracks as the irradiation power increased. Microhardness test showed that hardness increased toward the center of the welded zone and as the irradiation power increased, the range of hardness increased was expanded. CONCLUSION: The optimal laser irradiation power was the key to achieved superior mechanical properties joints.
出处
《上海口腔医学》
CAS
CSCD
2004年第5期416-420,共5页
Shanghai Journal of Stomatology
