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通过腐蚀磨损实验研究了下贝氏体球墨铸铁材料的腐蚀磨粒磨损行为,分析了影响腐蚀磨损失重率的主要因素.采用SEM和TEM对磨损表面特性进行了分析,根据磨损表层纵剖面的显微硬度研究了材料表层在腐蚀磨损过程中的形变硬化效应,结合下贝氏体球墨铸铁的电化学行为研究了载荷对耐腐蚀性能的影响.结果表明,下贝氏体球墨铸铁的腐蚀磨损机理为化学腐蚀失重和犁沟式磨粒磨损.载荷的提高对表面粗糙度、材料表面与磨粒之间的摩擦力以及磨粒压入材料表面的深度有显著的影响,从而导致磨粒磨损失重率显著上升.较高的载荷作用下,材料表面出现分层组织和条带状石墨,形成局部微型原电池,促使腐蚀速率提高,同时分层组织的疲劳断裂也将促使失重率进一步提升.载荷的增加使得基体中残留奥氏体内部出现大量位错的缠结,促进材料表面硬化,在一定程度上提高了材料的耐磨性能.当载荷从10 N增至200 N时,腐蚀磨损失重率从0.16 g/(cm2·h)增至0.42 g/(cm2·h).当粗糙度Ra由0.12μm增大到5.20μm时,腐蚀电流密度从0.56 m A/cm2上升至5.62 m A/cm2.下贝氏体球墨铸铁的腐蚀磨损失重曲线可分为3个阶段,分别为磨损初期的点接触加速磨损阶段、磨损中期的面接触过渡磨损阶段、磨损后期的疲劳磨损阶段.
The corrosive abrasive wear behavior of lower bainitic nodular cast iron was studied by corrosive wear test and the main factors influencing the corrosive wear weight loss rate were analyzed.The wear surface characteristics were analyzed by SEM and TEM.According to the significant The effect of load on the corrosion resistance of the lower bainite ductile iron was studied by the electrochemical behavior of the lower bainite ductile iron.The results show that the corrosion and wear mechanism of the lower bainite ductile iron For chemical corrosion weight loss and furrow wear.Impression of the load on the surface roughness, the friction between the material surface and abrasive particles and abrasive particles into the surface of the depth of the material have a significant impact, resulting in abrasive wear loss Rate increased significantly.Under high loading, stratified structure and ribbon-like graphite appeared on the surface of the material to form local miniature galvanic cells, which promoted the corrosion rate, meanwhile the fatigue fracture of the stratified structure would also promote the weightlessness rate to further increase. Increase the matrix so that there is a large number of dislocations within the retained austenite, promote material surface hardening, to some extent High wear resistance of the material increased from 0.16 g / (cm2 · h) to 0.42 g / (cm2 · h) when the load was increased from 10 N to 200 N. When the roughness Ra was increased from 0.12 μm The corrosion current density increased from 0.56 m A / cm2 to 5.62 m A / cm2 when the thickness increased to 5.20 μm. The corrosion wear loss curve of the lower bainitic nodular cast iron could be divided into three stages, Wear stage, mid-wear surface contact transition wear stage, the wear and tear of the late stage of wear and tear.