Direct deposition of low-cost carbon fiber reinforced stainless steel composites by twin-wire arc spray

[Display omitted] Metal matrix composites (MMCs), combining the unique advantages of two or more constituents, have been recognized as a promising structural material system. Particularly, MMCs reinforced by carbon fibers (CFs) have opened new material design routes towards increased strength-to-weight ratios. Here, we demonstrate a low-cost one-step deposition of CF reinforced stainless steel (CFRSS) composites by twin-wire arc spray on low-alloy steel (LAS) substrates. The CFs are self-assembled and grow coherently, up to 100 s of μm in length, along the splat-domain boundaries with enhanced bonding to their vicinals through partial oxidation. Structural and electrochemical studies reveal a pitting corrosion of the CFRSS layer in aqueous NaCl (3.5 wt.%) electrolyte and the corrosion passivation is apparently larger than that of the LAS substrate. Both the micro- and nano-hardness of the CFRSS layer are improved to over 4 times higher than that of the LAS substrate. These property enhancements indicate that this low-cost one-step process could revolutionize protective coatings on LAS against corrosion and/or erosion under aggressive conditions.