Effect of the δ phase on the hot deformation behavior of Inconel 718

✍ Scribed by H. Yuan; W.C. Liu

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 750 KB
• Volume: 408
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2005.08.126

✦ Synopsis

Hot compression tests at different temperatures and strain rates were performed on Inconel 718 solution treated as well as solution treated and then aged at 900°C for 1–24h in order to investigate the effect of the δ phase on hot deformation behavior. A hyperbolic-sine Arrhenius-type equation was used to characterize the dependence of the peak stress on deformation temperature and strain rate. In the case of Inconel 718 with a large amount of the δ phase, the apparent activation energy was determined to be 458kJ/mol, which was slightly higher than the activation energy of 443kJ/mol for solution treated Inconel 718. The γ″/γ′ phases present in Inconel 718 prior to hot deformation enhanced the peak stress, but did not affect the peak strain. The δ phase present in Inconel 718 not only decreased the peak strain and the peak stress, but also promoted the flow softening after the peak stress.