激光封接玻璃与可伐合金的抗拉性能及其原理分析

Study on Tensile Strength and Mechanism of Glass-to-Kovar Alloy with Laser Welding

以普通玻璃与可伐合金为实验材料,利用先进制造技术激光透射焊接工艺对两者进行连接,采用拉伸试验机、扫描电镜研究了焊接接头的微观结构和力学性能;讨论玻璃与可伐合金激光连接机理。结果表明,随着激光功率工艺参数的调节,拉断力从9.7N增加到62.8N,针对封接试样断裂失效、裂纹等问题,发现焊接接头断口形貌对力学性能有很大的影响;焊接接头微观形貌明显观察到新物质的形成。通过能谱分析得出连接两种材料的主要物质为铁硅化合物,中间物质决定了两种材料的激光封接性。

The paper reports an experimental study of welding of dissimilar materials between transparent glass and Kovar alloy by advance manufacturing technology; Laser transmission welding. The process was that laser beam went through the upper transparent glass, and then was absorbed by the lower bottom alloy. The microstructure and mechanical properties of welded joint were studied by scanning electron microscope （SEM） and tensile testing. The mechanism of laser welding process between glass-to-Kovar alloy was studied. The results show that with the regulation of laser process parameters （power）, breaking strength increases from 9.7 N initially to 62.8 N. Taking the problems of fracture failure and crack of the welded samples into consideration, it is found that fracture morphology of welded joint of samples have a great influence on mechanical properties during the welding process. A new compound is formed in the welded interface of two dissimilar materials, and the new chemical substance analyzed by energy dispersive spectrometer （EDS） is Fe-Si Compound, which was considered as the key-materials for a good glass-to-Kovar alloy joint.