| Aluminum based metal matrix composite (Al MMCs) materials with SiC particle reinforced as excellent capability engineering materials have high strength, good wear resistance, excellent elevated temperature, high stiffness. However the welding property of AL MMCs is poor, it's difficult to obtain high joint strength. The application of Al MMCs has been restricted by the low joint strength. In order to apply the Al MMCs into industry, it's necessary to study the reliable bonding technology. It's paramount significance to investigate the bonding method of SiCp/6061Al MMCs.The particle segregation in the joint region hasn't been observed when TLP bonding of Al MMCs using 10 m thickness copper foil, according with the theory of Z. Li. The effect of joint property is the oxidation on surface of the AI MMCs. When TLP bonding with pressure can avoid the effect of oxidation, obtain excellent joint property. Oxidation wasn't observed in the joint region by microanalysis. The process of transient liquid phase(TLP) bonding of 6061A1 MMCs using 10urn thickness copper foil has been studied. By the experiment, the best technology parameters for the TLP bonding have been obtained. The result is that, pressure of 2MPa, bonding temperature of 853K, holding time of 120 minutes, the average shear strength is up to 156.5MPa, 75.6% of the shear strength of base metal.It's the first time to deposit copper film on surface of Al MMCs by magnetron sputtering, and embed Al MMCs into the sputtering region of Al target. Inlaid target sputtering to remove oxide scale on surface of Al MMCs at first, then another copper target sputtering, copper film was deposited on the inlaid target. The technology parameters of deposition on surface of Al MMCs have been studied. TLP bonding of 6061A1 MMCs using deposition copper film as interlayer with the best parameters, the joint shear strength is up to 158.7MPa, 169.1MPa, 76.7%, 81.7% of the base metal shear strength.The microstructure, structure, composition, phase of joint region, and the microstructure and composition of fracture have been analyzed using the equipment of Metallurgical microscope, SEM, EDS, XRD and binary eutectic phase diagram for the Al-Cu system and diffusion theory. Effects of parameters (pressure, temperature, holding time) of TLP bonding of Al MMCs on the joint shear strength have been studied. Experimental and theoretical basis for joint with excellent mechanical properties havebeen provided.Copper has been deposited on surface of the Al MMCs as interlayer by magnetron sputtering, TLP bonding of Al MMCs with these interlays, the joints shear strength of TLP bonding using deposited film was as much as the joint shear strength of TLP bonding using Cu foil. Removing the oxidation on the surface before deposition, Copper was coated by magnetron sputtering as TLP bonding interlayer. The shear strength was 7.6% higher. There wasn't any oxidation in the joint region, and the structure was as same as the structure of base metal.When TLP bonding with proper pressure, the oxidation on the surface of Al MMCs wasn't the primary effect of the properties of the joint. TLP bonding using the deposited film markedly increased the joint shear strength... |
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