Similarities and Differences in Main Characteristics Between Transient Liquid Phase Bonding and Brazing Process

The similarities and differences in main characteristics between transient liquid phase (TLP) bonding and brazing process are compared in the following aspects:bonding process,solidification,oxide disruption,interlayer and filler metal,constituent parts of joint,formation and disappearing of brittle phase,effects of pressure,mechanisms of strengthening joint.The following key points are pointed out especially.(1)Careful selection of interlayer is a precondition to get a TLP bonded joint or a brazed joint.(2)The wettablity of filler metal on base metal is the key point in brazing process,because it is the precondition and main approach to make joint strong.(3)A sufficient diffusion of melting point depressant (MPD) elements into base metal and a suitable change of composition of interlayer due to loss of MPD elements by diffusion are the vitals to get a successful TLP bonding,because the essential reason for liquid zone widening,oxide disruption,isothermal solidification and homogenization of bond region is the diffusion of MPD elements.