Controlling microstructure of FeCrMoBC amorphous metal matrix composites via laser directed energy deposition

Highlights: • Directed energy deposition (DED) of FeCrMoBC alloy produces tunable microstructures. • Changing DED parameters tailor microstructures by altering cooling rates. • Hardness values ranging from 650 to 1400 HV achieved using same feedstock material. • Fe-based amorphous metal matrix composites were produced with DED. -- Abstract: Fe-based amorphous coatings are typically known for their high hardness and wear resistance and are often applied using thermal spraying techniques. When cladding these materials, using laser directed energy deposition (DED), it becomes possible to vary the cooling rate to create unique microstructures. Herein, it is demonstrated that a common FeCrMoBC coating alloy, typically known for its high hardness, can be fabricated into a variety of microstructures using DED, including an amorphous metal matrix composite with a soft dendritic phase and intrinsic toughening mechanism. The work offers the promise of using DED to fabricate custom claddings with high toughness as well as providing a potential route for creating ductile-phase-reinforced metallic glass composites using additive manufacturing.