Effect of Strain Hardening on Precipitation Kinetics in ATI 718Plus

Abstract:

ATI 718Plus components are manufactured by forging a wrought billet in stages to obtain the desired geometry and microstructure. Parts are then heat treated to optimized proportions of γ’ and η phases. η phase is a plate-like phase that precipitates on the grain boundaries of ATI 718Plus, similar to δ phase in Inconel 718. However, the complete kinetic behaviour of η phase precipitation during forging and heat treatment is still not fully understood. This paper investigates the effects of strain hardening on η phase precipitation kinetics in ATI 718Plus. This is achieved through the use of isothermal hot compression tests and heat treatment. Strain hardening was found to affect the η precipitation kinetics considerably. The results reported are a contribution to a fuller understanding of this important process

• Periodical: Materials Science Forum (Volume 907)
• Pages: 167-172
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.907.167
• Online since: September 2017
• Authors: Bilal Hassan*, Yann Jansen, Sebastien Nouveau, Jonathan Corney
• Keywords: ATI 718Plus, Eta Phase, Precipitation Kinetics, Strain Hardening, η Phase

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