Hastelloy X, process and heat treatment influence on microstructure and mechanical properties
Hastelloy X is a material available as an alloy for castings, hot-rolled/forged material and, since a few years back, as a material for additive manufacturing by laser powder bed technology. The material is typically delivered in a solution heat-treated condition. Standard parameters for the solution heat treatment (2150°F / 1177°C) followed by rapid cooling. It is acknowledged that temperatures lower than 1177°C may cause precipitation which, in turn, may affect ductility of the material.
The current work focusses at comparison of the material properties of Hastelloy X between the available standard delivery conditions with laser powder bed fusion additive manufactured material. Solution heat treatment and hot isostatic pressing has been conducted and the tensile and fatigue behaviour of the additively manufactured material is evaluated for the different heat treatment conditions. A metallographic assessment is performed and the metallographic quality is evaluated.
Results for the different manufacturing processes and heat treatment variants are presented. The microstructure / mechanical property relations are discussed.