EffectSofSBrazingSTemperatureSonSMicrostructureSandSPropertiesSofSSparkSPlasmaSBrazedSJointSofS5A06SAluminumSAlloy

Abstract:

5A06 aluminum alloys are widely used in the precise manufacturing structures such as liquid-cooling and waveguide components because of high strength, excellent corrosion resistance as well as good thermal conductivity and machinability. In this paper, spark plasma brazing by using Al-Cu-Si-Ni solder foil is performed to realize the joining of 5A06 aluminum alloy. The influence of brazing temperature on microstructure and mechanical properties of brazed 5A06 alloy joints was investigated. The results show that at the bonding temperature of 510~530℃, pressure of 4MPa and holding time of 10min conditions, the tensile strength of welded joint increase with temperature increasing. The maximum tensile strength is 152 MPa, wherein ductile fracture surface mainly composed of fine and homogenous dimples is obtained. Under the combined effect of low melting point solder, welding pressure, pulse electric field and short holding time, the brazing zone is getting thinner while matrix grains are finer and brittle phases are more dispersed. Meanwhile, the interfacial atomic diffusion and reaction are enhanced that the microscopic metallurgical bonding strengthened by Mg2Si, Si particles is obtained.

Key words:brazing temperature; 5A06 aluminum alloy; spark plasma brazing; microstructure; mechanical properties