Study On Metallic Brazing Filler And Brazing Processes Of 6063Al Matrix Composites With High Content Of SiC

High volume fraction of SiC particles reinforced aluminium matrix composites has a broad market prospect because of its excellent performance. However there exists a critical problem of connection reliability for brazing of this aluminium matrix composite. Connection of the composite material is more difficult than single homogeneous material due to its particularity and complexity of the microstructure. Brazing has been currently widely used in connection of composite material. So it is of certain theoretical and practical significance to design and prepare a solder for high volume fraction of SiC particle reinforced aluminium matrix composites and to develop reasonable soldering process.A suitable brazing filler metal used to bonding the parent metal of the SiCp/Al6063 composites is developed in this paper. And the best soldering process for this brazing filler metals is worked out.The microstructure of the brazing filler metals and the brazing welding joint is observed using XRD, SEM, EDS, TEM, and DTA. The main results are showed below:Rapid solidification not only reduces the liquidus temperature of solder effectively, but also improves the wettability of solder. With the increase of Ti content, toughness of solder foil decrease because of the increase of Ti(AlSi)3 content, and shear strength of the joint first increases and then decreases. Research results indicated that the maximum strength could be obtained with the solder, namely, AlSi5.25Cu26.7 ternary eutectic alloy, which was puting Ti content of 2% in.In the same conditions, shear strength of the brazing joint increases with the rising of temperature, and increases with the extension of heat preservation time. A good connection of SiCp/Al6063 could be achieved by the rapid solidification of the solder. The best brazing technique system is that the parent metal of the SiCp/Al6063 and solder are kept under vacuum of 3×10-3 Pa at 580?, heated and preserved for 50 min, and then braze welding are carried out. The shear strength of 109.5MPa could be obtained for the brazing welding joint of the parent metal of the SiCp/Al6063 composites and the solder.