Anocrystals And Ordinary304Stainless Steel Surface Wetting Properties

Materials with low surface energy own self-cleaning, drag reduction, friction reduction, anti-pollution etc. Thus, materials with low surface energy have wide prospects in these fields. Under normal circumstances, materials with lower surfaces can be prepared in two ways:the first way is using a low surface energy material to modify rough surface; the second is to change the surface roughness. According to the methods already proposed, the materials with low surface energy have been successfully prepared now, but these methods require special processing equipment and more complex process.The relationship between surface roughness and the wetting properties was studied through the measurement of surface contact angle, advancing angle and receding contact angle of nanocrystaline and conventional polycrystalline304stainless steel, and their surface roughness. The contact angles of nanocrystalline304stainless steel were larger than those of conventional polycrystalline304stainless steel, while the contact angle hysteresis of nanocrystalline304stainless steel were less those of conventional polycrystalline304stainless steel, which proved nanocrystalline304stainless steel has lower surface energy, and which is more conducive to the hydrophobic nature and more stable. The relationship between roughness and wetting properties was investigated by confocal microscopy, roughness tester, and X-ray photoelectron spectroscopy, for surfaces with different roughness. Because the surfaces in this work was not modified, the wetting properties of nanocrystalline304stainless steel and conventional polycrystalline304stainless steel are intrinsic performance.The surfaces of nanocrystalline304stainless steel and conventional polycrystalline were modified by chemical/electrochemical etching (two-step manufacturing hydrophobic surface). The etching time of two-step manufacturing hydrophobic surface is1-2order of magnitude shorter than that of a single-step method of chemical or electrochemical etching, and the crystal form is not restricted for two-step manufacturing hydrophobic surface, and the electrochemical corrosion current density of two-step manufacturing hydrophobic surface decreases one order magnitude of the power. Therefore, two-step manufacturing hydrophobic surface could be used in large-scale industrial production.