Effect of Casting Diameter and Heat Treatment Process on Microstructural Evolution and Mechanical Properties of Fe۵۵-XCr۱۸Mo۷B۱۶C۴NbX(X=۰,۳) Ribbons and Nanostructured Rods

One-step and two-step annealing techniques were used to examine the relationship between microstructure and mechanical properties during compression tests in iron-based ribbons and nanostructured ۱- and ۲.۵mm cylindrical rods. The X-ray diffraction, microstructural, and mechanical results showed that substituting Nb for Fe had a minor effect on glass-forming ability but increased the formability index. The novel two-step annealing process resulted in a remarkable formability index of ۱۶.۶۲ GPa, yield stress of ۲۸۳۰ MPa, ultimate strength of ۳۸۶۶ MPa, and ۴.۳% plastic strain. A ductile nanosized α-Fe framework and boron-containing nano precipitations, which caused Zener pinning effect, were responsible for these novel mechanical properties.

Keywords:

: Casting , Rapid solidification , Heat treatment , Microstructure , Mechanical properties