Production of amorphous and nanocrystalline iron based coatings by electro-spark deposition process

An iron-based alloy electrode with a high glass-forming ability was deposited on an austenitic stainless steel substrate by electro spark deposition at a range of process parameters. Overall, six specimens were coated with different parameters. Field emission scanning electron microscopy (FESEM) microstructural studies and X-ray diffraction (XRD) were conducted on the coated samples. The results showed that the coating structure is amorphous at low total heat input values, but at high values of total heat input, an extremely fine-grained or likely nanocrystalline structure is obtained. Hardness of amorphous coating was measured to be 1300 Vickers, which is similar to the hardness of the same Fe48Cr18Mo7B16C4Nb7 amorphous alloy.