Influence of deposition parameters on the corrosion resistance of metals deposited by cold gas spraying

Influence of deposition parameters on the corrosion resistance of metals deposited by cold gas spraying

 

Cold spraying is a thermal spraying technique with an expanding field of application. As the powder is not melted during deposition, this technique is particularly suitable for the oxide-free deposition of metallic coatings. This is particularly interesting when a corrosion protection layer is required that also has good electrical conductivity, as is the case in polymer electrolyte membrane (PEM) electrolyzer. We investigate the influence of deposition parameters on three different materials deposited by cold gas spraying: titanium, niobium and tantalum.

The microstructure was analysed using scanning electron microscopy (SEM), the phase composition was determined through X-ray diffraction (XRD) and the contact resistance was measured. Subsequently, a corrosion test wit PEM anode side like conditions was carried out before the sample was re-examined to assess its corrosion stability.

We also show that it is possible to apply a corrosion protection layer to fragile expanded metals with a thickness of around 125 µm using cold spraying without damaging them. The coated expanded metals were then installed in a PEM electrolyzer on a laboratory scale and tested for their durability.