Vacuum brazing tests on aluminum were carried out to find out a suitable pretreatment. Specimens were brazed into tee type joint using Al-12% Si filler alloy. The alloy sheet was pre-inserted between vertical and horizontal members. The results indicate that inserted type brazing enables sound fillet formation when the surface treatment is pertinent. Chemical treatments were not recommended as a pretreatment for vacuum brazing of aluminum, however, emery paper grinding was guaranteed satisfactory fillet formation. The effect of emery paper roughness was also studied. It was found that rougher papers than 1000 grades were preferable but grinding by fine papers of 1200 and 1500 grades were not adequate.
Transactions of JWRI 6 (1), 139-144, 1977-06