Improving the mechanical properties of tantalum carbide particle-reinforced iron-based composite by varying the TaC contents

Abstract

Tantalum carbide (TaC) is known to have a remarkable influence on mechanical properties of metal-matrix composites thanks to its high hardness, high melting point, excellent wear resistance, and chemical stability. In order to obtain excellent comprehensive mechanical properties of iron-based composites, the effects of the TaC particle contents on the iron-based composites were investigated in this study, and the TaC particle phase was formed by the chemical reaction between the tantalum and carbon sources during the synthetic procedure. The TaC particle reinforced iron-based composites were fabricated by mechanical alloying using high-energy ball mill followed by a subsequent hot pressing (HP) at 1250 °C under 60 MPa, and without any subsequent heat treatment process. The formed crystalline phases, evolved microstructures, and element distribution of the TaC/Fe composite were studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The densification, hardness, compressive performance, and wear resistance of the as-fabricated TaC/Fe composites were measured using the Archimedes' method, Rockwell hardness tester, electromechanical universal testing machine, and abrasion wear tester, respectively. Combining mechanical alloying method with hot pressing process, the TaC/Fe composites with high elastic modulus, good yield strength, high compressive fracture strength and acceptable strain can be obtained through the control of the content of TaC reinforcement originated from the in situ reaction during hot pressing.