The invention discloses a vacuum
brazing connection method for C / C radiating fins and Ti tubes. The method comprises the following specific process steps:
grinding and
polishing a Ti
pipe to remove an
oxide film, and performing
vacuum drying for later use after ultrasonic cleaning; tiZrNiCu
alloy powder and TiC
powder with the
mass percent being 3%-5% are mixed, then
alcohol is added for ball milling for 15-18 h, the
powder is dried and sieved after ball milling, then an oily binder with the
mass percent being 8%-10% is added into sieved powder, the mixture is stirred into paste
brazing filler metal, then the portion between the connecting surfaces of the C / C cooling fins and the Ti
pipe is filled with the paste
brazing filler metal, assembling is conducted, and the C / C cooling fins and the Ti
pipe are assembled. And the
assembly part is clamped by a
graphite clamp and then placed in a
vacuum furnace, the temperature is increased to 920 DEG C at the speed of 4-7 DEG C / min under the vacuum degree not lower than 1 * 10 <-3 > Pa, heat preservation is conducted for 10-20 min, and finally connection is completed after the furnace is cooled to the
room temperature. The connecting method is simple in process, safe, free of
pollution, low in cost and high in reliability, and the problems that in the
welding process, due to large
residual stress, a connecting piece cracks, and wettability between
base metal is insufficient are effectively solved.