Latent heat of crystallization and precursor film induced superior wettability of tungsten heavy alloy by Cu Ti based amorphous alloys

Abstract We synthesized a series of Cu Ti based crystalline and amorphous brazing filler metals (BFMs) and further investigated the microstructure characteristics and melting features for comparison. The presence of precursor film together with latent heat of crystallization showed a significant effect on the enhanced wettability of amorphous BFMs/tungsten heavy alloy (WHA) system. The wetting and spreading mechanism were addressed in a view of atomic adsorption and diffusion. The brazed joints showed effective interface bonding and high shear strength, especially at elevated temperature (up to 364 MPa at 400 °C). This study demonstrates the great superiority and feasibility of amorphous brazing filler metals in the joining of WHAs.