Effect of hip cooling rate and post-hip heat treatments on IN718 microstructure and mechanical properties

Research output: Chapter in Book/Report/Conference proceedingConference contribution


Colleges, School and Institutes

External organisations

  • Ceit-IK4 Technology Center and Tecnun
  • IRC in Metallurgy and Materials


The influence of hot isostatic pressing (HIP) cooling rate on the microstructure and mechanical properties of Inconel® 718 (IN718) superalloy has been studied. As-HIPped IN718 powder and post-HIP heat treated samples developed at different HIP cooling rates have been analysed. Electron back scattered diffraction (EBSD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been used to study the microstructure and assess changes in precipitate sizes caused by the different HIP cooling rates, which also influence mechanical properties. Hardness measurements and tensile tests at both room temperature and 650 ºC have been carried out on these samples and the results have been related to their microstructure. It has been found that higher amount of precipitates is obtained in as-HIPped materials developed at slower HIP cooling rates and in consequence the strength is higher and ductility is lower. However, after post-HIP heat treatments the behaviour changes and the microstructure and mechanical properties are very similar as long as profuse precipitation is avoided in as-HIPped samples.


Original languageEnglish
Title of host publicationEuro PM 2018 Congress and Exhibition
Publication statusPublished - 1 Jan 2020
EventEuropean Powder Metallurgy Congress and Exhibition, Euro PM 2018 - Bilbao, Spain
Duration: 14 Oct 201818 Oct 2018

Publication series

NameEuro PM 2018 Congress and Exhibition


ConferenceEuropean Powder Metallurgy Congress and Exhibition, Euro PM 2018