Fabrication of Hard WC + Cu + La2O3 Coating on Ti–6Al–4V Alloy Using Reverse EDM Process

Titanium and its derivative alloys have multiple and wider applications in the field of additive manufacturing, aerospace engineering, biomedical industries, chemical industries, etc. Biocompatibility, high stiffness, high specific strength, low density, etc. are the properties that enable its vast use in different industries. Furthermore, its application in the field of abrasion and wear and tear-like situations is due to its low hardness, and high wear rate-like properties. After its failure, it must be superseded, but this adversely cause heavy cost to the industries. In this regard, different researchers are modifying the surface of titanium alloy. So that it can withstand the harsh condition and cut the cost of industries. The major intention of this work is to obtain a hard coating on titanium alloy using WC + Cu + La2O3 as the electrode material through the reverse EDM processing route (also known as electric discharge coating). The electrode is prepared using a hot mounting press and the coating is made under the reverse polarity of EDM with distilled water as a dielectric fluid. Coating layer thickness (CLT), Tool wear rate (TWR), Material deposition rate (MDR) and microhardness are the recorded output responses. 325 µm of maximum coated layer thickness is obtained at 11 A peak current, whereas, the maximum microhardness of the coated layer is noted as 726 HV0.1 at 13 A current which is twice that of the substrate Ti–6A–4V plate. MDR increases with a rise of peak current up to 11 A thereafter it starts decreasing because high spark energy remelts the earlier solidified coating layer. TWR increases with a rise in peak current as a consequence of higher spark energy between the electrodes.