Study of the influence of heat treatment on the metallurgical characteristics of the IN625 alloy

The nickel super alloy 625 can be used for mechanical applications on the solid solution state but has its applicability in aeronautic, aerospace, marine, chemical and petrochemical industries when improvement on mechanical resistance by age-hardening treatments are performed. In this study the grain growth, precipitation and phase transformation were evaluated in a commercial superalloy 625. Grain growth at different temperatures and the correspondent phase transformation were evaluated during the solution. A comparison between single aging at different temperatures and an innovative double aging heat treatments combination were investigated by SEM, hardness test and tensile tests. As a consequence of heat treatment in nickel alloys the high temperature can influence negatively reducing the corrosion resistance, an important characteristic for this group of alloy that was evaluated according the ASTM G28 method A.