O. Covarrubias, O. Elizarraras, Frisa Aerospace SA de CV, Santa Catarina, Mexico
Alloy 909 is a Ni-Fe-Co alloy which main properties include a low coefficient of thermal expansion and high strength when this material is exposed to elevated temperatures. These properties make this alloy suitable for applications like turbine engine components. These properties are promoted by appropriate heat-treatment processes, which include Solution and Aging procedures, affecting microstructural characteristics like grain size and presence of intergranular and transgranular precipitates. This job summarizes the results of several trials to determine best conditions to promote desired mechanical and microstructural properties. Validation by tensile, hardness and stress-rupture testing is complemented by microstructural analysis, including electronic microscopy. Obtained information allowed the proposal of a method of manufacture which since its implementation, no metallurgical deviation has been reported.
Summary: Alloy 909 is a Ni-Fe-Co material which main characteristics make it suitable for high-temperature applications. These properties are promoted by appropriate heat treatment processes, which have a direct effect on microstructural characteristics. Several heat treatment procedures applied to this alloy were performed; these procedures were validated by mechanical (tensile, hardness and stress-rupture testing) and microstuctural testing (optical and electronic microscopy)to determine best process conditions to promoted desired properties.
