Troisiéme Conférence Européenne sur les Matériaux et les Procédés Avancés
J. Phys. IV France 03 (1993) C7-1135-C7-1140
Determination of brazed joint constitutive law by inverse methodG. LOVATO1, F. MORET1, P. LE GALLO1, G. CAILLETAUD2 and P. PILVIN2
1 CEREM/Laboratoire de Génie des Matériaux, CENG, 85X, 38041 Grenoble cedex, France
2 Centre des Matériaux de l'Ecole des Mines de Paris, UA 866 du CNRS, BP. 87, 91003 Evry cedex, France
An important parameter often neglected for the calculation of residual stresses in brazed ceramic/metal assemblies is the joint constitutive law. In situ camber measurements on a model system (axisymmetric TZM/InCuSil ABA/316L samples) performed using a special vertical dilatometer during the whole brazing thermal cycle are compared with results of FEM calculations based on published filler metal constitutive laws. A strong disagreement is observed. Actual constitutive law of the joint is determined from these measurements using a numerical inverse method. Calculated displacements are fully consistent with experimental ones. True solidification temperature of the joint is determined. The identified constitutive law of the joint exhibits a low flow stress from solidification temperature to 320°C.
© EDP Sciences 1993