Induction melting, casting, and weldability of a group IAB iron meteorite

Abstract

Future construction of large-scale space structures will need to exploit natural space resources for raw materials such as iron from asteroids, which is expected to be a key element due to its availability in near-Earth objects. Although the relative availability of iron-nickel asteroids makes them attractive candidates for space manufacturing, they contain defects and inhomogeneous concentrations of elements such as carbon, phosphorous, and sulfur, along with brittle intermetallic phases, cracks, and voids, that limits their usefulness in their native state. Refinement of the meteoritic metal microstructure and chemistry will be required to render them useful as structural elements that can be fabricated by casting, thermomechanical processing, or welding. This study investigates the vacuum induction melting and casting of a Canyon Diablo Group 1AB-MG coarse octahedrite meteorite demonstrating, as a first step, that cast material can be produced with a refined and more homogeneous microstructure. However, additional metallurgical refinement is still needed to reduce the phosphorous and sulphur content to produce high quality meteoritic steels or alloys for space construction.