摘要
通过微观组织及力学性能分析、大气腐蚀失重速率计算、表面锈层形貌观察、锈层截面电子探针元素分析等方法,对添加Ni、Cr、Cu耐候元素的输电输电铁塔用Q355BNH耐候角钢在大气环境中的腐蚀行为进行了研究,并与普通碳钢进行了对比。研究表明,两种试验钢均为珠光体+铁素体组织,并且Q355BNH试验钢组织更加均匀规整;Q355BNH试验钢抗拉强度为559 MPa,屈服强度为443 MPa,断后伸长率为31.3%,断面收缩率为74.1%,性能略高于对比试验钢;添加耐候元素后,Q355BNH在大气环境中1~2月周期下的腐蚀速率要高于对比钢,之后腐蚀速率降低,元素分析表明Q355BNH试验钢能更快地形成Cr元素富集的致密性锈层,对基体的保护作用更好,之后周期内两种试验钢的腐蚀速率均趋于稳定;Q355BNH试验钢的锈层表面形貌中裂纹、孔洞的程度较轻,平整度与致密度更高,即锈层阻碍基体进一步被侵蚀的能力更强,具有更好的耐大气腐蚀能力;Q355BNH试验钢的锈层截面更加均匀,致密性更高。
The corrosion behavior of Q355BNH weather-resistant angle steel for transmission towers with Ni,Cr and Cu weathering elements in the atmospheric environment was studied by microstructure and mechanical property analysis,atmospheric corrosion loss rate calculation,surface rust layer morphology observation,rust layer cross-section electron probe element analysis,etc.,and compared with ordinary carbon steel.The results show that both test steels have pearlite+ferrite structure,and the Q355BNH test steel structure is more uniform and regular.The tensile strength of the Q355BNH test steel was 559 MPa,the yield strength was 443 MPa,the elongation after breaking was 31.3%,and the section shrinkage rate was 74.1%,which was slightly higher than that of the comparison test steel.After adding weather-resistant elements,the corrosion rate of the Q355BNH in the atmospheric environment under the 1~2 month cycle was higher than that of the comparison steel,and then the corrosion rate decreased,and the elemental analysis showed that the Q355BNH test steel could form a dense rust layer enriched by Cr elements faster,and the protection effect on the matrix was better,and the corrosion rate of the two test steels tended to be stable in the cycle.Q355BNH the degree of cracks and holes in the surface topography of the rust layer of the test steel is lighter,and the flatness and density are higher,that is,the rust layer has a stronger ability to hinder the further erosion of the matrix and has better atmospheric corrosion resistance;Q355BNH the rust layer section of the test steel is more uniform,and the density is higher.
作者
王娇娇
刘宏春
刘泳
李民
陈红卫
安治国
Wang Jiaojiao;Liu Hongchun;Liu Yong;Li Min;Chen Hongwei;An Zhiguo(HBIS Materials Technology Research Institute,Shijiazhuang 050023,Hebei)
出处
《河北冶金》
2023年第10期15-19,35,共6页
Hebei Metallurgy
基金
河北省自然科学基金高端钢铁冶金联合项目(E2022318003)。
