CAJ | 학술논문

为了研究钎料元素Al+Zn对镁合金钎焊接头显微组织与抗剪强度的影响，以两种Al-Mg-Zn镁合金钎料对变形镁合金AZ31B进行了高频感应钎焊，研究两种Al-Mg-Zn镁合金钎料的显微组织、钎焊接头的显微组织及力学性能。结果表明：随着钎料中Al+Zn元素含量(质量分数)的增加，钎料的固相线和液相线温度也随之增加；在钎焊过程中两种 Al-Mg-Zn 镁合金钎料与母材 AZ31B 均发生强烈合金化作用，在钎缝中均生成α-Mg+β-Mg17(Al,Zn)12离异共晶组织，钎料的原始显微组织消失，且随着钎料中Al+Zn元素含量的增加，钎焊接头中的金属间化合物相β-Mg17(Al,Zn)12的体积分数和显微硬度也随之增加，同时钎焊接头力学性能随之降低。钎焊接头的断裂形式均为沿晶脆性断裂，断裂均产生在金属间化合物相β-Mg17(Al,Zn)12处。
위료연구천료원소Al+Zn대미합금천한접두현미조직여항전강도적영향，이량충Al-Mg-Zn미합금천료대변형미합금AZ31B진행료고빈감응천한，연구량충Al-Mg-Zn미합금천료적현미조직、천한접두적현미조직급역학성능。결과표명：수착천료중Al+Zn원소함량(질량분수)적증가，천료적고상선화액상선온도야수지증가；재천한과정중량충 Al-Mg-Zn 미합금천료여모재 AZ31B 균발생강렬합금화작용，재천봉중균생성α-Mg+β-Mg17(Al,Zn)12리이공정조직，천료적원시현미조직소실，차수착천료중Al+Zn원소함량적증가，천한접두중적금속간화합물상β-Mg17(Al,Zn)12적체적분수화현미경도야수지증가，동시천한접두역학성능수지강저。천한접두적단렬형식균위연정취성단렬，단렬균산생재금속간화합물상β-Mg17(Al,Zn)12처。
In order to research effect of Al+Zn elements of the filler metal on microstructures and mechanical properties of magnesium alloy brazed joint, the wrought magnesium alloy AZ31B was joined using two kinds of Al-Mg-Zn filler metals by high-frequency induction brazing mode. The microscopic structure of the filler metal, microscopic structure and the mechanical properties of the brazed joint were studied. The results show that the solidus and liquidus temperatures of the filler metals are light increment when the contents of Al+Zn elements of the filler metals increase. The α-Mg+β-Mg17(Al,Zn)12 divorced eutectoid structure forms in the brazing region due to the intensive alloying between the molten two kinds of Al-Mg-Zn filler metals and the solid base metal AZ31B occurred in the brazing process. The original microscopic structure of the filler metals disappears completely after the brazing process. As contents of Al+Zn elements of the filler metal increase, the volume fraction and microhardness of intermetallic compoundβ-Mg17(Al,Zn)12 increase too, and the shear strength of the brazed joints decreases. The overlapped joints exhibit intergranular fracture mode, the fracture comes fromβ-Mg17(Al,Zn)12 hard brittle phase.