Cu₂O+Cu+Ag-Cu-Tiインサート法で得られるAl₂O₃と鋼接合部の継手強度特性

抄録

Bonding of Al₂O₃ coated with Cu₂O+Cu to steel using Ag-Cu-Ti brazing filler metal was conducted in a vacuum furance and joint strength between 96%, 99% Al₂O₃ and 29Ni-16Co, 13Cr, 18Cr-8Ni steel was investigated in comparison with conventional Ag-Cu-Ti method,
Joint strength (shear strength) was evaluated in relation to position of fracture at joint strength test and calculated thermal stress of joint after bonding.
Main results obtained are as follows.
(1) Position of fracture at joint strength test was in Al₂O₃ when thermal stress (tension) in Al₂O₃ was high such as Al₂O₃/13Cr, 18Cr-8Ni steel joint and in brazing filler metal when thermal stress (tension) in Al₂O₃ was low such as Al₂O₃/29Ni-16Co steel joint for both bonding methods.
Average value of joint strength indicated high value when position of fracture was in brazing filler metal.
Coefficient of variation indicated low value and Weibull shape parameter indicated high value when position of fracture was in brazing filler metal which had no brazing defect.
Al₂O₃/29Ni-16Co steel joint was excellent for bonding combination.
(2) Excellent joint properties (average value of joint strength, coefficient of variation, Weibull shape parameter) were obtained at Cu₂O+Cu+Ag-Cu-Ti bonding method for Al₂O₃/29Ni-16Co stell joint.
96% Al₂O₃ was recomended because it had good spreadability of Ag-Cu-Ti brazing filler metal and maximum values of joint properties were obtained.