The influence of Al:Nb ratio on the microstructure and mechanical response of quaternary Ni-Cr-Al-Nb alloys

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:612

Article

Mignanelli, P. M.¹  Jones, N. G.¹  Hardy, M. C.²  Stone, H. J.¹ 

[1] Univ Cambridge, Dept Mat Sci & Met, Cambridge CB3 0FS, England

[2] Rolls Royce PLC, Derby DE24 8BJ, England

关键词: Nickel-based superalloys;    Microstructure;    Gamma prime;    Ageing;    Electron microscopy;   

DOI  :  10.1016/j.msea.2014.06.021

来源: Elsevier

【 摘 要 】

The influence of Al:Nb ratio on the microstructure and properties of Ni-Cr-Al-Nb alloys has been investigated following long-term exposure at elevated temperatures. The gamma' volume fraction, size and lattice misfit were seen to increase with a larger Al:Nb ratio, although these changes resulted in reduced hardness. The change in the critical resolved shear stress (CRSS) associated with strong dislocation coupling was determined to be the dominant strengthening mechanism and increased with decreasing Al:Nb ratio. A distribution of tertiary gamma' was observed to be necessary in maximising the mechanical properties of these alloys. (C) 2014 The Authors. Published by Elsevier B.V.

【 授权许可】

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