20SiMn在单相液流和液固双相流中的空蚀行为

利用超声振动空蚀实验机研究了20SiMn在蒸馏水、3％NaCl单相液流和含有3kg／m^3石英砂液固双相流中的空蚀行为，探讨了腐蚀因素对单相液和液固双相流中金属材料空蚀的影响。结果表明：在液固双相流空蚀中，存在电化学腐蚀、固相颗粒的冲蚀员以及空蚀力学破坏三者的交 用。受到固相颗粒的冲蚀磨损后，金属材料表面平缓，腐蚀因素促进在单相液流和液固双相流中金属材料的空蚀破坏，但腐蚀因素引起液固双相流中空蚀失重相对增加理小于其引起单相液流中空蚀失重相对增加量。

CAVITATION EROSION OF 20SiMn IN SINGLE LIQUID AND LIQUID - SOLID TWO - PHASE MEDIUM

The effect of corrosion on cavitation erosion on 20SiMn in single liquid (distilled water) and liquid-solid two-phase medium (silica sand-containing distilled water) was investigated by using ultrasonic vibration facility. The mediums were added with 3% NaCl in order to study the effect of corrosion factor on cavitation erosion. The degradation mechanism was analyzed by SEM observation and profile measurement. The results showed that there was synergistic interaction among electrochemical corrosion, solid particle erosion and cavitation erosion. The surface profile of the material gets smoother in liquid-solid two-phase medium than in single liquid after cavitation erosion. Corrosion has remarkable influences on cavitation erosion of 20SiMn in both single liquid and liquid-solid two-phase medium. And the cavitation erosion comparative enhancement by corrosion in two-phase medium was less than that in single liquid medium.The phenomenon was explained by morphology and profile observation.