| Abstract Scope |
The Fe-10Ni alloy system exhibits superior levels of toughness, strength, and ballistic resistance across a wide range of cooling rates and service temperatures that have distinguished it as a potential replacement for high-strength low-alloy (HSLA) steels commonly used in shipbuilding. Existing studies have characterized the microstructure and properties of the Fe-10Ni base plate and consumable under a variety of fabrication conditions, but existing research on the properties of additively manufactured parts is limited. Hot-wire laser additive manufacturing (HWLAM) is a low heat input, energy-efficient process that can produce complex geometries with comparable or superior mechanical properties to parts produced by casting or arc additive manufacturing. HWLAM has the potential to produce fully dense, defect-free Fe-10Ni parts that retain the remarkable properties observed in existing studies on the alloy.
This study characterized the microstructure and mechanical properties of Fe-10Ni builds produced by HWLAM. Microstructural variety throughout the builds, a result of multiple thermal cycles, was characterized using EBSD, grain size measurement, microhardness measurements, and scanning electron microscopy. Impact toughness of the bulk material was assessed, and defects were characterized using RT and micro-resolution UT. Based on these results, the structure-property relationships for Fe-10Ni HWLAM builds and the potential for naval applications were discussed |