Figure 3: Mechanical resistance of electrodeposited TO films on stainless steel.

(a) Indentation Young’s modulus (black line) and hardness (blue line) of AISI 304 stainless steel before and after electrodeposition of porous TO films as a function of deposition time. (b) Bending of 100-μm-thick stainless-steel plate coated with the electrodeposited TO porous film: (i) before bending, (ii and iii) bending in both inward and outward directions and (iv) after 10 times bending in both directions. (c) A top view snapshot from a particle abrasion experiment with 2 mm YSZ particles impinging on the samples during test. In each experiment, 35 g of YSZ media was used. Superhydrophobic TO samples were mounted near-normally to the falling particles and the test was repeated 10 times by alternating YSZ particles of 0.8 and 2 mm diameter. (d) Bright field reflection optical image of the sample after 10 particle abrasion tests. Labels ‘I’ and ‘II’ indicate areas abraded by 0.8 and 2 mm particles, respectively. The contrast is mainly due to slight dent reflecting the light differently. The dent on the surface caused by impingement with lighter YSZ particles was hardly observable in optical microscope images. Scale bar, 200 μm. (e,f) SEM images of the sample shown in d displaying surface damage produced by 0.8 (e) and 2 mm (f) YSZ particles, respectively. Scale bar, 10 μm. Inset images (scale bar, 100 nm) show a higher magnification of the abraded area.