摘要
Abstract
In order to meet the demand of engineering,the development of 8.8～23.8 mm quenched and tempered L415QS steel plate for acidid environment were carried out.The composition design of low C,low Mn,Cr,Ni,Cu composite alloying was adopted,LF+RH dual treatment was used in the steel making process,and the combination control of finishing rolling temperature,start cooling temperature,cooling water group opening mode,and final cooling temperature was used in the rolling process.The heat treatment adopts offline quenching+tempering treatment.Results showed that the heat treatment was offline quenching+tempering treatment,and L415QS steel plate with uniform structure was obtained.The yield strength of the 8.8 mm and 23.8 mm steel plates is more than 460 MPa,the tensile strength is more than 550 MPa,and the yield strength ratio is less than 0.90.The hardness of the steel plate is uniform,with a hardness difference of 1.7～3.2HV10 between the same plate;-60℃impact energy is more than 200 J,-40℃DWTT shear area is more than 85%.No cracking were found in the HIC and SSC resistance tests of the steel plate.The metallographic structure is mainly composed of tempered bainite.The performance of the trial steel plate meets the project design requirements.关键词
管线钢/调质热处理/L415QS/酸性环境/力学性能Key words
pipeline steel/quenching and tempering heat treatment/L415QS/acidic environment/mechanical properties分类
能源科技
