Interface structure and mechanical property of aluminum cooler vacuum brazing joint
(1.上海市上海交通大学材料科学与工程学院
2.School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
3.School of Materials Science and Engineering, Shandong University, Ji’nan 250061, China)
2.School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
3.School of Materials Science and Engineering, Shandong University, Ji’nan 250061, China)
Abstract: A kind of aluminum cooler was manufactured by means of vacuum brazing technique, and the cooler was examined by hydraulic pressure test. The result indicates that the test pressure of the cooler can reach 15 MPa. The fracture of the brazing joint belongs to the mixture type. There are secondary cracks, dimples, cleavage plane and grain-boundary features on the failure surface. The cracking process of aluminum cooler is as follows. The cracks are initiated on the interface, then expand under sub-critical state. When the stress on the remained zone reaches the maximum notch tensile strength of the brazing joint or the crack length reaches the critical value that the brazing joint fracture toughness property permits, the cooler will break sharply.
Key words: aluminum cooler; vacuum brazing; hydraulic pressure test; fracture