Mechanical properties of one-step in situ synthesized NbC-Fe composite coating

A NbC-Fe composite coating on an iron matrix was synthesized through one-step in situ synthesis using a pure niobium (Nb) plate and gray cast iron (HT300). The coating surface morphology, microstructure, and composition were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The synthesized NbC-Fe composite coating consisted of fairly agglomerated and uniformly sized (similar to 200 nm) NbC particulates accounting for 95% of the volume fraction. The coating thickness was similar to 60 mu m. Coating nanohardness and elasticity modulus values were 20.69 +/- 0.32 GPa and 438.24 +/- 3.38 GPa, respectively. Further, scratch testing, measured using a scratch tester under a progressive load of 0-100 N, revealed no delamination or peeling over the tested loads. Therefore, the coating offered the iron matrix effective protection from serious abrasion. The present study discusses the synthesis of an excellent scratch resistant NbC-Fe composite coating on an iron matrix. (C) 2016 Elsevier B.V. All rights reserved.