Effects Of Wettability And Electric Field On Ultrasonic Cavitation Damage

As one of the main failure forms of hydraulic machinery,cavitation has always been the research hotspot of researchers.Deeply exploring the mechanism of cavitation erosion and improving the technology of inhibiting cavitation erosion can effectively reduce the damage of cavitation erosion.Because the cavitation phenomenon involves multi-disciplinary,micro and complex influencing factors,its occurrence mechanism is not clear,which inevitably limits the development of cavitation inhibition technology.Existing studies have shown that surface wettability has an important effect on cavitation erosion,but related studies are few and scattered,and the effect of applied electric field on cavitation erosion is rarely reported.Therefore,the influence of surface wettability and applied electric field on cavitation erosion was studied in this paper,in order to provide a basis for further exploring the mechanism of cavitation erosion,which is also of great significance to the development of cavitation erosion suppression technology.In this paper,the effects of surface wettability and applied electric field on cavitation erosion of 45^#steel were studied by ultrasonic vibration cavitation erosion experimental device.The influence of different wettability particles on the surface cavitation erosion of 45^#steel was analyzed,and the cavitation erosion failure law of45^#steel in different media under different voltages was explored,and the failure mechanism was discussed.The main results were as follows:（1）The surface wettability of 45^#steel and micro particles had an important influence on cavitation erosion.Prolonging cavitation time,adding Si O₂micro particles and hydrophobic properties of Si O₂micro particles or 45^#steel surface will lead to more serious cavitation damage.The surface wettability of micro particles had a greater impact on cavitation erosion than that of 45^#steel sample.When both the sample surface and the micro-particle surface were hydrophobic,cavitation damage was the most obvious.The wettability of sample surface and microparticle surface had no effect on the composition of cavitation erosion products.（2）The effect of applied electric field on cavitation damage was significant.When the vibrating head and the sample were connected to the two poles of voltage respectively,the opposite phenomenon of aggravation or inhibition of cavitation damage would occur,and the effect of aggravation or inhibition would change with the change of voltage value.For the three different liquid media,cavitation damage had the same effect with voltage variation,but the action mechanism was different,which was mainly related to the charged properties of cavitation bubble and microparticle surface.At the same voltage,compared with the hollow erosion of deionized water,Si O₂particles can promote the cavitation erosion,while Al particles can inhibit the cavitation erosion.