Aging effect on the wettability of stainless steel

摘要: Abstract Commercial metals have recently been reconsidered as useful materials for functionalized surfaces with controlled wettability, yet the intrinsic wettability of various metal remain uncertain. In this study, we report that a stainless steel (Type 304) surface exhibits time-dependent transition, initially from hydrophilic state to relatively hydrophobic state. The static contact angle water droplet was monitored on polished every 24 h, and rapid increase in angle, 44° 81°, found during first three days. reached 98° 40 To clarify main factor causing phenomenon, compared angles stored four different environments five days, where oxygen moisture levels were controlled. From difference depending amount oxygen, conclusion is likely cause aforementioned phenomenon. Finally, demonstrated micro-grooved whose initial superhydrophilicity became superhydrophobic after 30