EFFECT OF HAFNIUM CONTENT ON MORPHOLOGY EVOLUTION OF γ′ PRECIPITATES IN P/M Ni–BASED SUPERALLOY
ZHANG Yiwen 1,2, WANG Fuming 1, HU Benfu 3
1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083
2. High Temperature Material Institute, Central Iron and Steel Research Institute, Beijing 100081
3. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083
Cite this article:
ZHANG Yiwen WANG Fuming HU Benfu. EFFECT OF HAFNIUM CONTENT ON MORPHOLOGY EVOLUTION OF γ′ PRECIPITATES IN P/M Ni–BASED SUPERALLOY. Acta Metall Sin, 2012, 48(8): 1011-1017.
Abstract The cubic γ′ particle morphology evolution was studied during long time aging process in a powder metallurgy (P/M) Ni–based superalloy with Hf addition. The results show that, during long time aging process, the cubic γ′ particle splits into a doublet of plantes or an octet of cubes. The octet of cubes with low energy is a preferred shape, it splits no longer. The γ/γ′ lattice misfit varies with different Hf contents. The growth or coarsening process of γ′ precipitate can be roughly divided into interface controlling and strain controlling stages, the γ′ precipitate morphology is greatly influenced by the elastic interaction energy between γ′ particles.
Supported by National Key Basic Research Program of China (No.2010CB631204) and Sino–Russian Intergovernmental Cooperation in Science and Technology Project (No.CR14–20)
