|About this Abstract
||MS&T21: Materials Science & Technology
||Additive Manufacturing of Metals:
ICME Gaps: Material Property and Validation Data to Support Certification
||An ICME Approach for Designing Appropriate Heat Treatments in Additively Manufactured Nitrogen Atomized 17-4PH Stainless Steel
||James Zuback, Mark Stoudt, Daniel Gopman, Maureen Williams, Carelyn Campbell
|On-Site Speaker (Planned)
Appreciable amounts of dissolved nitrogen in 17-4PH stainless steel introduce metallurgical challenges by stabilizing austenite and inhibiting the formation of martensite during post-process heat treatment. Alloy chemistry variations within specifications can add further complexity and significantly alter the heat treatment response. Here, an integrated computational and experimental approach is used to elucidate the competing factors for designing appropriate post-processing routes beyond ordinary heat treatments for wrought materials. The work focuses on tailoring martensite fractions for a given alloy composition prior to aging. A suite of Calphad based tools are used to track nitrogen distributions, simulate secondary phase precipitation, and predict transformation temperatures during post-processing steps. These results guide targeted experiments to test heat treatment designs, and extensive microstructural characterization provides validation and feedback for improving model predictions. Findings suggest that a universal heat treatment protocol is not suitable for the variety of powder feedstocks and additive manufacturing process combinations available.