2006 Volume 24 Issue 3 Pages 273-280
The development of TLP-bonding process for Ni-base superalloy, Inconel 718 has been carried out using the Bayesian Expert System for TLP-bonding. In order to skip the homogenising treatment, alloy system for insert metal was selected as Ni-Mo-Cr-Nb-Si-B system. The evaluation factors introduced as an index of bonding performance of an insert metal involved the melting point of insert metal, hardness and formability of brittle phases in the bond layer. The chemical composition of Ni-3.0Mo-6.4Cr-4.7Nb-2.0Si-1.0B (mass%) was determined as the optimal composition of an insert metal. The processing parameters have been optimised with three evaluation factors; the joint strength, reduction of area and toughness. The optimal bonding condition was determined as 1459K×3.3ks. Brittle phases were not formed in the bond layer by using a newly developed insert metal, and the joint strength and toughness was over 80% of the base metal properties.