New approaches for transient liquid phase diffusion bonding of aluminium based metal matrix composites

Abstract

AbstractAbstractThree new approaches for the transient liquid phase (TLP) diffusion bonding of aluminium based MMCs have been developed.The first method is based on the simultaneous combination of TLP diffusion bonding and isostatic compression. The joining of 8090 Al/SiC composite using this method and a 3 μm thickness copper inter layer resulted in bonds with shear strengths of up to 221 MPa (85% of the shear strength of the parent material). The second method consists of low pressure TLP diffusion bonding in a vacuum followed by isostatic pressing in air. The highest bond strength for a 359 Al/SiC composite, joined using a 7 μm thickness copper interlayer, was 242 MPa which is 92% of the parent material. This value is the highest bond strengthfor Al MMCs that has been reported to date. In the third method (a variant of the second method), low pressure TLP diffusion bonding was followed by hot isostatic pressing (hipping) without encapsulation. The preliminary results are encouraging, and it is shown that the method can be usedfor the fabrication of intricate components with minimal deformation.