Synthesis and characterisation of a novel Fe-based nanocomposite by mechanical alloying and spark plasma sintering

To improve low hardness and poor corrosion resistance of the Fe-based alloys, Fe–Ti–Al–B–Si–C–P–Cr novel alloy was prepared using mechanical alloying and spark plasma sintering (SPS). Two types of mills, including of high-energy planetary (HEP) and SPEX(S) ball mills (BM) were used to reach the solid solution. Mechanical alloying by the HEP route led to the formation of the Fe(α) phase after 60 h, while its milling after 15 h by high-energy SPEX mill led to the formation of the Fe(α) solid solution. After sintering of as-milled powders by SPS, the composite of Fe (α)/nanocrystalline was obtained. The micro-hardness of the HEP–SPS and the S–SPS samples obtained about 689.5 ± 0.15 and 2068.5 ± 0.18 HV0.3, respectively. The lowest corrosion current density and the highest polarization resistance were related to the HEP–SPS sample and was calculated to be 0.51 µA/cm2 and 41.668 KHz/cm2, respectively.