冲击形式产生的冲蚀、空蚀和腐蚀联合磨损试验研究

舰船等海洋运输装备在海水中行驶时,船体表面受到含沙海水的冲蚀磨损,舰船行驶速度变化引起的空蚀磨损,以及海水的腐蚀磨损,因此舰船表面材料的破坏形式是冲击式的冲蚀、空蚀和腐蚀联合磨损。为了研究联合磨损的影响因素,研制冲蚀、空蚀和腐蚀联合磨损试验台,并实验研究沙粒浓度、沙粒尺寸、含盐浓度以及冲蚀速度对45钢试件的联合磨损影响规律。实验结果表明:冲蚀、空蚀和腐蚀联合磨损程度强于冲蚀和空蚀交互磨损或单纯腐蚀磨损,在较低的沙粒浓度和较低的含盐浓度条件下,金属材料联合磨损质量损失与沙粒浓度、沙粒尺寸、含盐浓度和冲蚀速度均成正比关系。磨损面形貌分析表明:随着沙粒浓度、沙粒尺寸、含盐浓度、冲蚀速度的增加,试件表面的冲蚀沟和空蚀孔的磨痕深度和面积增大,而在人造海水中,试件表面不仅存在冲蚀沟和空蚀孔,还产生了腐蚀坑。

Experimental Study of Combined Wear for Slurry Erosion,Cavitation Erosion and Corrosion Caused by Fluid Impact

The surface of ships and other marine transportation equipment is eroded by sandy seawater when running.With the change of the speed of ships,cavitation erosion will occur.Because seawater has corrosive effect on metal materials,the damage forms of surface materials of ships are combined wears for slurry erosion,cavitation erosion and corrosion.In order to study the influencing factors of the combined wear,an experimental set up for combined wears was developed.The effects of sand concentrations,sand sizes,salt concentrations and impact speed on the combined wear of steel 45 were studied experimentally.The results show that the combined wear for slurry erosion,cavitation erosion and corrosion is stronger than the interactive wear for slurry erosion and cavitation erosion or the simple corrosion wear.Under the conditions of lower sand concentration and lower salt concentration,the mass loss of metal materials for combined wears is proportional to the sand concentration,sand size,salt concentration and impact speed.The analysis of wear surface morphology shows that with the increase of sand concentration,sand size,salt concentration and impact speed,the depth and area of wear marks of erosion ditches and cavitation holes on the surface of specimens are increased.In artificial seawater,there are not only erosion ditches and cavitation holes on the surface of specimens,but also corrosion pits.