A microstructural study of alloy 718 plus™

Abstract

A microstructural study using metallographic, x-ray diffraction, and Edax analyses techniques was carried out on alloy 718 Plus samples which were in various thermal conditions. Results of this study showed that the strengthening phase is gamma prime which grows larger with increasing time of exposure. A delta phase nucleates and grows as the gamma prime phase becomes larger. No gamma double prime is found in the standard heat treatment and no αCr, sigma or Cr carbides are found in samples exposed for 2500 hours at 732°C (1350°F) in Alloy 718 plus while αCr forms in as little as 1000 hours at 704°C in Alloy 718.