Electro-deposition metallic tungsten coatings in a Na2WO4–WO3 melt on copper based alloy substrate

The tungsten coating was prepared by electro-deposition technique on copper alloy substrate in a Na2WO4–WO3 melt. The coating's surface and cross-section morphologies as well as its impurities were investigated by XPS, SEM and line analysis. Various plating durations were investigated in order to obtain an optimal coating's thickness. The results demonstrated that the electro-deposited coating was compact, voidless, crackless and free from impurities. The tungsten coating's maximum Vickers hardness was measured to be 520 HV. The tungsten coating's minimum oxygen content was determined to be 0.018 wt%. Its maximum thickness was measured to be 1043.67 μm when the duration of electrolysis was set to 100 h. The result of this study has demonstrated the feasibility of having thicker tungsten coatings on copper alloy substrates. These electrodeposited tungsten coatings can be potentially implemented as reliable armour for the medium heat flux plasma facing component (PFC).

► The tungsten coating (>1 mm) was obtained by electro-deposition method in molten salt.
► Different thickness tungsten coatings were obtained by using different durations.
► Good performance of coating was obtained when pulse parameters were modulated.