油套管钢P110S的腐蚀磨损交互作用

Interaction of Corrosion and Wear for Oil Well Tube Steels P110S

为了持续研究油套管钢的腐蚀磨损行为,揭示其腐蚀磨损机理,采用失重法和电化学法测试了油套管钢P110S在不同浓度氯化钠溶液中的腐蚀磨损行为。结果表明:对以索氏体和贝氏体为基本组织的油套管钢P110S而言,在不同浓度的氯化钠溶液中,腐蚀与磨损呈正交互作用;在所测试的3种浓度(0.01,0.10,1.00mol/L)中,P110S在0.10 mol/L氯化钠溶液中的失重最大;电化学研究显示,腐蚀磨损前随着氯化钠溶液浓度的增加,P110S的自腐蚀电位逐渐降低,在3种浓度氯化钠溶液中腐蚀磨损一定时间后,P110S的自腐蚀电位基本相同;P110S在0.01 mol/L和1.00 mol/L氯化钠溶液中的腐蚀磨损形貌呈现零散的鹅卵形冲击坑,坑底部存在着严重的塑性变形和局部断裂,而在0.10 mol/L的氯化钠溶液中,小的冲击坑遍布试样表面,坑密且浅。

The corrosive wear of oil well tube steels P110 S in NaC l solution was investigated by electrochemical tests and weight-loss tests at room temperature and atmospheric pressure.Results showed that positive synergism existed between corrosion and wear in NaC l solution for the oil casing P110 S with sorbite and bainite as the basic organization. The maximal weight-loss rate was obtained in 0. 10 mol / L NaC l solution. According to the results of the electrochemical tests,the corrosion potential was decreased with the increase of concentration of NaC l in solution before the corrosive wear. However,when the corrosive wear las-ted for 9 h,the corrosion potentials were similar in 3 kinds of NaC l solutions. Moreover,some large and scattered impacted-pits emerged on the surface of P110 S in 0. 01 mol / L and 1. 00 mol / L NaC l solution after the corrosion-wear for 9 h,and notable plastic deformation and local fracture were observed at the bottom of pits. Besides,impacted-pits with little size densely distributed on the surface of P110 S in 0. 10 mol / L NaC l solution.