Effect of micro B on wettability of Cu-P based quenching filler metals

Three different components of the Cu-P based filler metal foils were prepared by single-roll rapidly-cooled equipment. The melting feature and structure were analyzed with DTA and XRD methods. The wettability of Cu-P based filler metals on copper was studied. The results showed that, compared with the conventional filler metals, the quenching filler metals had lower melting temperature and narrower melting temperature range. The quenching filler metal containing 0.03% B had the lowest liquidus temperature and the narrowest melting temperature range. The structures of the quenching filler metals with 0.03wt% B and 0.04% B were amorphous. In the same process conditions, the quenching filler metal contained 0.03wt% B had best wettability on copper. As with brazing temperature and time increased, the wettability of Cu-P based quenching filler metal appears increased first and then decreased. Compared with conventional brazing filler metals, the wettability of quenching filler metal has been improved significantly.