Microstructure has a direct influence on the mechanical properties of metallic materials. An alloy's microstructure is a result of its inherent chemistry, manufacturing process, and heat treatment. Historically, alloys have been developed and optimized to meet their intended requirements in conjunction with a specific manufacturing process, such as casting, forging, or sheet forming. Additive Manufacturing (AM) is a relatively new process that offers significant benefits for rapid design and implementation and is currently being considered by many industries including aerospace. Many of the already existing aerospace alloys are capable of being processed into viable components by a variety of AM methods. Current expectation is that research in AM processing will lead ultimately to development of unique microstructures that will have a significant impact on the alloy's mechanical properties. This paper discusses the microstructure and properties of traditional aerospace alloys processed by AM with respect to potential use in gas turbine engine applications. In the past few years, Honeywell has evaluated the AM capability of a wide variety of aerospace alloys. Mechanical property data were generated to determine process capability in comparison to the corresponding cast or wrought versions and to identify potential failure modes in their design and applications. The materials were manufactured in a laboratory environment in the absence of any AM material specifications and controls. Currently, AM lacks an established industrial supply base and the required standards, specifications, and quality system to meet aerospace requirements.
Yang, L., Hsu, K., Baughman, B., Godfrey, D., Medina, F., Menon, M., & Wiener, S. (2017). Microstructure, Mechanical Properties, and Design Considerations for Additive Manufacturing (pp. 45–61). https://doi.org/10.1007/978-3-319-55128-9_3