20SiMn低合金钢和0Cr13Ni5Mo不锈钢的多相流损伤行为

对水轮机用金属材料20SiMn低合金钢和0Cr13Ni15Mo不锈钢进行旋转圆盘仪空蚀和冲刷磨损单元和组合多相流损伤实验。结果表明，20SiMn低合金钢和0Cr13Ni15Mo不锈钢的冲刷磨损及空蚀和冲刷磨损联合作用损伤累积质量损失－时间曲线均呈线性关系，空蚀和冲刷磨损联合作用对材料造成的损伤显著高于空蚀和冲刷磨损单独作用，空蚀和冲刷磨损的交互作用在空蚀和冲刷磨损联合作中起重要的作用；在空蚀和冲刷损联合作用中，液体空化及随后的空泡溃灭改变了流体中固相颗粒的运动方向，引起固相颗粒的流速增加和攻角改变，从而加剧了固相颗粒对材料表面的损伤。

CAVITATION-ABRASION BEHAVIOR OF 20SiMn AND 0Cr13Ni5Mo STEELS IN MULTIPHASE FLOW

Cavitation-abrasion behaviors of 20SiMn and 0Cr13Ni5Mo steels in multiphase flow have been investigated by using a rotating disc equipment. The eroded surfaces were observed by scanning electron microscopy. The profiles of eroded surfaces were measured by a profilograph, and roughness values Ra were calculated based on the profile curves. The results showed that abrasion and cavitation-abrasion cumulative mass loss exhibited linear relations with experiment time, cavitation-abrasion damaged materials much more seriously than single action of cavitation erosion or abrasion, and the synergism between cavitation erosion and abrasion played an important role in cavitation-erosion; the flowing direction of solid particles were changed for vapour bubbles produced in cavitated liquid collapsing, and this increased the flowing speed and changed incidence angles of solid particles so that the damage to materials was promoted.