流体机械叶轮常用材料冲蚀与空蚀交互磨损特性研究  

Study on Abrasion Properties of Common Materials for Fluid Mechanical Impeller at Interactive Erosion and Cavitation Wear

作　　者：庞佑霞[1,2] 李彬[1] 刘厚才[1] 唐勇[2] 

机构地区：[1]湖南科技大学机电工程学院,湖南湘潭411201 [2]长沙学院先进设计与制造技术研究所,湖南长沙410003

出　　处：《润滑与密封》2013年第12期23-26,45,共5页Lubrication Engineering

基　　金：国家自然科学基金项目(5097532);湖南省教育厅重点项目(10A009);湖南省自然科学基金项目(13JJ6082);湖南省"十二五"重点学科建设项目

摘　　要：模拟流体机械冲蚀与空蚀交互磨损工况,通过对比材料的绝对失重量与试验时间的变化曲线、24 h试验的磨痕演变规律以及SEM微观形貌,研究Q235、45#和40Cr钢及HT200铸铁4种叶轮常用金属材料的磨蚀特性。结果表明:在冲蚀与空蚀交互磨损下,材料的失重量与磨损时间接近正比;试件的磨痕沿水流方向,在空蚀孔两边呈彗星状分布;沙粒对Q235等塑性材料微切削过程中,动能转化为材料的塑性变形功,使材料产生塑性流动,形成犁沟状磨痕;对于脆性材料HT200,空泡溃灭和沙粒的冲击超过其弹塑性变形极限,使材料产生微裂纹、微体积疲劳剥落,形成蜂窝状蚀坑。相同硬度下,塑性材料耐交互磨蚀性能优于脆性材料。Through simulating turbine working condition on interactive erosion and cavitation wear, the abrasion charac- teristics of Q235, 45 and 40Cr steel,and HT200 cast iron were studied, and the change curves between material＇s abso- lute weight loss with experimental time were obtained. The wear scar evolution of four materials during the 24 h experiment was compared and the specimen mierostrueture was observed by SEM. The results show that the weight loss of material is a- bout in direct proportion to the abrasion time under interactive wear;the specimen wear scar along the flow direction takes a comet formation distribution on both sides of the cavitation hole ; during the process of sand micro-cutting on plastic mate- rial such as Q235 steel, the kinetic energy is converted to plastic deformation work, which causes material plastic flow and forms furrow-like wear scar;brittle material like HT200 cast iron, the bubble collapse and sand impact exceeds its elastic- plastic deformation limit, as a result, micro-cracks, fatigue spalling and honeycomb pits are generated for material;the wear resistance of plastic material is better than that of brittle material at the same hardness.

关 键 词：叶轮材料 冲蚀与空蚀 交互磨损 微切削 疲劳剥落 

分 类 号：TG174.2[金属学及工艺—金属表面处理]