Transient Liquid-Phase Bonding in the Ni-Al-B System

Published

November 1, 2000

Author(s)

Carelyn E. Campbell, William J. Boettinger

Abstract

Transient liquid phase (TLP) bonding experiments were performed using a Ni-10.3 at. % Al alloy and a Ni-10 at. %B filler material and the results were compared to simulations performed using the finite-difference diffusion code, DICTRA. For the simulations a thermodynamic assessment of the Ni-Al-B system was used to define the phase diagram and the thermodynamic factors of the diffusion coefficients. Composition-dependent diffusion mobilities were assessed for the ternary system. The limited amount of data for the mobility of boron in the literature required further adjustment of its values based on the measured liquid widths. In the base material, the simulations qualitatively predicted the observed precipitation and later dissolution of the intermetallic t phase (Ni(sub20)Al(sub3)B(sub6)) during bonding. The predicted liquid widths are in good agreement with the experimentally measured liquid widths. The calculated Al composition profiles also correspond to the measured Al profiles, particularly in the matrix phase. This research demonstrates the potential for modeling the formation of spurious phases during TLP bonding of practical superalloy systems.

Citation

Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science

Volume

31A

Issue

No.11

Pub Type

Journals

Keywords

finite diffusion couple, Ni-Al-B diffusion mobilities, time-dependent diffusion, transient liquid phase bonding

Citation

Campbell, C. and Boettinger, W. (2000), Transient Liquid-Phase Bonding in the Ni-Al-B System, Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science (Accessed December 4, 2024)