QT1100连续油管钢的抗液固两相流冲蚀性能

采用含砂粒清水混合液(携砂液)对QT1100连续油管钢进行液固两相流冲蚀试验,研究了携砂液冲刷角度(15°,30°,45°,60°,75°,90°)、冲刷速度(2.4,7.2,12.0,16.9 m·s^(−1))、砂质量浓度(15,30,45,60,75 kg·m^(−3))、砂类型(尖角形天然石英砂、近圆形人工陶粒砂)和砂粒径(0.063~0.420 mm)对试验钢抗冲蚀性能的影响,分析了冲蚀损伤机理。结果表明:在试验参数下冲蚀后,试验钢均主要发生机械冲刷磨损,损伤机理均包括微切削和冲击挤压,其中小角度冲刷以微切削为主,大角度冲刷以冲击挤压为主。试验钢的冲蚀速率随着冲刷角度或砂粒径的增大先增大后减小,在45°冲刷角度或者0.15~0.18 mm粒径天然石英砂条件下试验钢的冲蚀损伤最大;冲蚀速率随着冲刷速度增大而增大,随着砂质量浓度增加先增大,当砂质量浓度为60 kg·m^(−3)时减小,随后快速增大;相较于近圆形人工陶粒砂,尖角形天然石英砂的冲蚀速率更大,对试验钢的冲蚀磨损更严重。

Si_3N_4-SiC复相耐磨材料的冲蚀磨损性能

以Si粉和SiC为原料,采用半干法冷等静压成型,通过反应烧结成功制备了Si3N4-SiC复相耐磨材料。并将其和95Al2O3耐磨陶瓷在以水和SiC混合颗粒为冲蚀介质实验条件下,进行液固两相流冲蚀磨损对比实验。结果表明:原料中Si粉加入量为40%～80%(质量分数)试样的耐冲蚀磨损性能优于95Al2O3耐磨陶瓷。原料中Si粉加入量为70%试样的耐固液两相流冲蚀磨损性能最好,在平均线速度分别为132和67m/min的实验条件下的冲蚀率分别仅为0.87%和0.30%。此外,通过SEM观察了冲蚀后试样的显微形貌,探讨了其耐液固两相流冲蚀磨损的机理。

Slurry erosion behaviors of P110 steel and chromizing coating in liquid-solid two-phase flow

A chromizing coating was formed on P110 oil casing tube steel (P110 steel) via pack cementation to improve its performance and increase the lifetime during operation. The slurry erosion behaviors of the P110 steel substrate and the chromizing coating were assessed in a liquid-solid two-phase flow condition. The results showed that the obtained coating exhibited higher surface hardness, lower mass loss, and lower slurry erosion rate than those of P110 steel. The chromizing treatment has significantly improved the surface hardness and slurry erosion resistance of P110 steel.