DIFFUSION BEHAVIOUR OF Hf IN Ni AND Ni_3Al
Hf在Ni和Ni3Al中的扩散行为

The Hf-containing alloy was selected as a interlayer for brazing and Transient-Liquid-Phase(TLP) bonding of single crystal superalloy, in which element Hf should diffuse as quickly as possible from bond to matrix phase. The objective of this investigation is to determine the diffusion behaviour of Hf in two matrix phases of superalloy,the Ni-rich solid solution(y)and intermetallic compound(Ni3Al). In present work,the diffusion coefficient, diffusion activity energy in two matrix phases, and their relation with temperature and Hfcontent are reported, which are useful to select a proper bonding condition.