80 mm厚DH36钢板厚度方向非对称冷却过程中的温度梯度及冷却后的显微组织和力学性能  

Temperature Gradient during Asymmetrical Cooling and Microstructure and Mechanical Properties after Cooling along Thickness for 80-mm-thick DH36 Steel Plate

作　　者：杜平 丁美良 曲锦波 DU Ping;DING Meiliang;QU Jinbo(Institute of Research of Iron and Steel,Shasteel,Zhangjiagang Jiangsu 215625,China)

机构地区：[1]江苏省(沙钢)钢铁研究院,江苏张家港215625

出　　处：《上海金属》2025年第2期54-58,共5页Shanghai Metals

摘　　要：制作了检测钢板冷却过程中厚度方向温度梯度的装置。测定了80 mm厚DH36钢板从正火温度水冷至400~650℃空冷过程中厚度方向的温度梯度,并模拟了钢板冷却过程中厚度方向温度随时间的变化,检测了钢板冷却后的显微组织和力学性能。结果表明:钢板上表面以下50 mm处温度高于40 mm处温度;距离上表面20 mm处的抗拉强度比40 mm处高17.11 MPa,比60 mm处高14.89 MPa;上表面以下50 mm处硬度最低,为145 HB,下表面硬度比上表面高4.1 HB,距离上表面20 mm处硬度比60 mm处高3.9 HB。钢板正火后冷却为非对称冷却,导致其力学性能和显微组织在厚度方向是非对称的。A device used to survey temperature gradient along thickness of steel plate during cooling was made.Temperature gradient along thickness of a 80-mm-thick DH36 steel plate during water cooling from normalizing temperature to a range of 400 to 650℃followed by air cooling was surveyed,the temperatures along thickness of the steel plate as a function of time during cooling were simulated,and the microstructure and mechanical properties of the plate after cooling was tested.The results indicated that(a)the temperatures at 50 mm from the upper surface were higher than that at 40 mm;(b)the tensile strength at 20 mm from the upper surface was 17.11 MPa higher than that at 40 mm and 14.89 MPa higher than that at 60 mm;and(c)the hardness at 50 mm below the upper surface was as the least as 145 HB,the hardness of the lower surface was 4.1 HB higher than that of the upper surface,and the hardness at 20 mm from the upper surface was 3.9 HB higher than that at 60 mm.The cooling of steel plate after normalizing was an asymmetric cooling,which led to the mechanical properties and microstructure along the steel plate thickness were asymmetrical.

关 键 词：中厚板 非对称冷却 温度梯度 差分方程 力学性能 

分 类 号：TG335[金属学及工艺—金属压力加工]