Internal stress of high tungsten content Ni-W alloy coatings

This study investigates the impact of current density on the microstructure, composition, and internal stress of Ni-W alloys electrodeposited in a citrate system. Using XRD, SEM, EDS, TEM, and XPS, it was found that tungsten serves as a solute in a Ni-W FCC structure oriented in the (111) direction. Increasing current density led to higher tungsten content and current efficiency. The addition of 2-Butyne-1,4-diol altered the carbon content, significantly reducing internal stress by promoting carbide formation near grain boundaries, which prevented coating shrinkage during hydrogen escape. This carbon enrichment improved the alloy's corrosion resistance.

Automated summary

This study investigated the influence of current density on the microstructure, composition, and internal stress of Ni-W alloys electrodeposited in a citrate system. The results showed that tungsten existed as a solute in a Ni-W FCC structure oriented in the (111) direction. Increasing the current density resulted in higher tungsten content and current efficiency. The addition of 2-Butyne-1,4-diol altered the carbon content and reduced internal stress by promoting carbide formation near grain boundaries, preventing coating shrinkage during hydrogen escape. This carbon enrichment improved the corrosion resistance of the alloy.