氧含量对银基粉状钎料熔化特性和钎焊接头性能的影响

Effects of Oxygen Content on the Melting Characteristics and Brazing Mechanical Properties of Silver-based Powder Brazing Filler Metals

通过第一性原理计算和试验等多种分析方法来研究氧含量对熔化特性以及钎焊接头力学性能的影响。结果表明,钎料的表观活化能随着钎料中氧含量的增加而增加,导致了熔化时间增加。随着钎料中氧含量的增加,钎焊接头的抗拉强度呈现非线性下降,为了确保钎料的良好性能,应该将钎料中的氧含量控制在200μg·g-1以下。根据疲劳试验结果,氧元素引起的钎焊缺陷被认为是裂纹的源头,该研究提供了氧含量对银基粉状钎料钎焊过程影响的详细机制。

Density functional theory(DFT) calculations and various analytical methods were employed to study the effects of increased oxygen content on the melting characteristics and brazed joint mechanical properties.The results reveal that the apparent activation energy of the filler metal increases with increasing the oxygen content,resulting in an increase in the melting time.The tensile strength of the brazed joints decreases nonlinearly with increasing the oxygen content in the filler metal.To ensure the good performance of brazing filler metals,oxygen content of the filler metals should be controlled less than 200μg·g-1.According to the fatigue testing results,the brazing defects induced by oxygen serve as a source of fracture cracks.This study provides a detailed mechanism of the effects of oxygen on the brazing process of the silver-based powder filler metals.