1990 Volume 8 Issue 4 Pages 503-509
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.