SCREEN-PRINTABLE OR DISPENSABLE ACTIVE BRAZING PASTES AND PROCESS FOR PRODUCING THE SAME

摘要

These active brazing pastes satisfy the requirements for screen printing or dispensing particularly well and are well suited for brazing one aluminum oxide ceramic body to another one or to a metal body. This can be done by means of respective regions of brazing paste applied by screen printing to the ceramic bodies, with the coverage of one region matching the coverage of the other region or by in-serting the metal body into a hole in the ceramic body and using a pad of brazing paste applied to the ceramic body and to the metal body by dispensing. The printable paste comprises as the active brazing material a hydrogenated powder of a Zr/Ni/Ti alloy or a Zr/Fe/Ti/Be alloy and as an organic vehicle poly(butyl-methyl methacrylate) or poly (n--decyl methacrylate) as the polymer and the camphor ketal of 2,2,4-trime-thylpentane-1,3-diol and/or 5-nonyl-methyl ether as the solvent for the polymer. The dispensable paste comprises as the active brazing material the same powder and as the organic vehicle a mixture of poly (butylmethyl methacrylate) dissolved in the camphor ketal of 2,2, 4-tri-methylpentane-1,3-diol as a first solvent, as a first com-ponent of the mixture and poly(butylmethacrylate) dissolved in 5-nonyl methyl ether, as a second solvent, as a second component of the mixture.