超声空化对Q235钢表面腐蚀行为的影响  

Effects of ultrasonic cavitation on surface erosion of Q235 steel specimens

作　　者：龙正[1] 刘秀梅[1] 

机构地区：[1]中国矿业大学机电工程学院,江苏徐州221116

出　　处：《中国科技论文》2013年第6期573-575,共3页China Sciencepaper

基　　金：国家自然科学基金资助项目(51209203);江苏省自然科学基金资助项目(BK2012131)

摘　　要：研究了在频率分别为20、28、40kHz的超声波作用下,Q235钢表面的空蚀过程。实验中900W超声波发生器用来产生超声波,并作用于固定在水槽中的试样表面。采用光学显微镜观察试样在不同空蚀阶段表面形貌的变化过程,并通过分析天平测量试样的质量变化。结果表明:随着超声波作用时间的增加,试样表面由光滑变为具有大量的麻点或针孔等形状凹坑的特殊形貌,且随着空蚀时间的进一步增加,凹坑的深度明显增大,相连成片,材料表面变为蜂窝形状;随着超声波频率的增大,试样表面凹坑数量和深度均增加,表面空蚀程度愈加明显。此外,试样质量随实验时间增加呈先减小后增大的趋势,质量损失率在0.2%到0.5%之间。研究结果为进一步揭示空蚀过程材料破坏机理提供了实验依据,同时也为开发新型抗空蚀磨损材料提供了参考。The cavitation erosion of Q235 steel specimens at different frequencies （20, 28, 40 kHz） was studied using 900 W ul- trasonic generator to generate ultrasonic effect at the sample surface fixed in a tank. The optical microscope was used to investi- gate morphological characteristics of samples at different stages of cavitation erosion, and analytical balance was adopted to meas- ure mass losses of the samples. The results indicated that both the density and depth of the pits increased with cavitation time in creasing, and a large number of pits connected in series. As the frequency increased, both the number and the depth of the pits on the surface increased. Furthermore, the quality of the samples firstly decreased and then increased over cavitation time. The mass loss rate of the samples ranged from 0.2 % to 0. 5 %. These results might help to reduce the erosion of materials and develop new materials which have high resistance to cavitation erosion.

关 键 词：超声空化 Q235钢 超声频率 表面冲蚀 质量变化 

分 类 号：TG174.3[金属学及工艺—金属表面处理]