Fabrication and dynamics of two layers vanadium carbide reinforced iron matrix surface composite

Abstract

Vanadium carbide particulates-reinforced iron matrix composites were prepared by in situ solid-phase diffusion method with different heat treatment times (30, 60, 120 and 240 min) at 1223 K, 1273 K and 1323 K after high temperature treatment at 1373 K for 5 min. The surface vanadium carbide layers (V2C layer and V8C7 layer) were characterized by means of scanning electron microscopy and X-ray diffraction. The kinetics of vanadium carbide layers showed that a parabolic relationship between carbide layer thickness and treatment time, which indicating that the composite layer's growth is controlled by diffusion. The apparent activation energy of V2C layer and V8C7 layer were 47.27 kJ/mol and 32.26kJ/mol, respectively.