防锈油对DP590钢腐蚀行为的影响

Effect of Antirust Oil on Corrosion Behavior of DP590 Steel

采用不同量防锈油对DP590钢进行涂装。通过透射电子显微镜(TEM)观察了DP590钢的微观结构;通过接触角测量仪、扫描电子显微镜(SEM)、盐雾腐蚀试验等研究了防锈油涂油量对DP590钢表面润湿性和耐蚀性的影响。结果表明:DP590钢组织主要由粗大的铁素体和少量马氏体组成,平行板条状马氏体穿插分布在铁素体内部,与铁素体交错形成类似纤维状双相混合组织;DP590钢表面的腐蚀坑主要为由夹杂物诱发的尺寸较小的点蚀孔和马氏体相与铁素体相之间电偶腐蚀形成的尺寸较大溃疡状腐蚀坑;随着涂油量的增加,DP590钢表面接触角呈现先增大后减小再增大趋势;防锈油在短期内对DP590钢表面具有较强的防护作用,按800 mg/m^(2+)中涂油量对DP590钢进行涂装,不仅能获得最好的防护作用,而且还可以节省防锈油的涂装成本。

DP590 steel was painted with different amount of antirust oil. The microstructur of DP590 steel was observed by transmission electron microscope(TEM). The effects of painting amount of antirust oil on surface wettability and corrosion resistance of DP590 steel were studied by contact angle measuring instrument, scanning electron microscope(SEM) and salt spray corrosion test. The results show that the microstructure of DP590 steel was composed of coarse ferrite and a little martensite. The lath martensite interpenetrated in the ferrite and was interlaced with ferrite to form a similar fibrous dual-phase mixed structure. The corrosion pits on DP590 steel surface were small pits induced by inclusion and large ulcerated pits formed by galvanic corrosion between martensite phase and ferrite phase. With the increase of antirust oil amount, the surface contact angle of DP590 steel first increased, then decreased and then increased. The antirust oil had a strong protective effect on the surface of DP590 steel in a short time. Painting DP590 steel with 800 mg/m^(2+) antirust oil could not only get the best protective effect, but also save the coating cost of antirust oil.