Effect of processing technique on the mechanical properties of a functionalized superhydrophobic silane

The need to test for the durability and capability of a coating before being subjected to service is highly important for engineering applications. Ultra-low indentation of nanohardness and nano-scratch are valuable methods of measuring durability and near-surface mechanical properties of thin films. AISI 304 stainless steel was coated with Repellix superhydrophobic coating using chemical vapor deposition (CVD) and atomic layer deposition (ALD) techniques at constant processing parameters. The deposited films were characterized through nanoindentation, nanoscratch, and water contact angle to establish the effect of coating technique on the mechanical properties of the thin films. The results established that the ALD deposition technique has better hardness but less wear resistance when compared to the sample produced using the CVD method. ALD also showed to have a lower contact angle in comparison with a coating deposited by CVD. Overall, it is expected that the substrate coated by CVD would outperform samples produced via ALD as regards to typical applications where good wear and corrosion resistance are required.