应用有限元方法模拟分析了控制冷却过程钢板厚度方向上温度和冷却速度的分布。结果表明,钢板表面冷却速度随着冷却的进行逐渐减小,而钢板中心冷却速度逐渐增大,其余位置的冷却速度先增大然后减小。分析了冷却时间、开始冷却温度、冷却水温度和水流密度对冷却速度和钢板表面与中心冷却速度差的影响规律,结果表明,冷却速度差随冷却时间的增加、开始冷却温度的升高和冷却水温度的升高而减小,随水流密度的增大而增大。试验结果表明,由于冷却速度不同,钢板厚度方向上的组织和晶粒尺寸不同,钢板表面出现了贝氏体组织,板厚度1/4处和中心为铁素体和珠光体,晶粒尺寸从表面向中心逐渐增大。
Temperature and cooling rate distribution in thickness direction of plate were analyzed with finite element method.The results show that surface cooling rate of plate decreases and center cooling rate of plate increases with the increase in cooling time,and it increases firstly and then decreases in the other position.The effect of cooling time,start cooling temperature,water temperature and water flow density on cooling rate and cooling rate difference of plate surface and center was investigated.The results show that cooling rate difference decreases with the increasing in cooling time,start cooling temperature and water temperature,and increases with the increasing in water flow density.The experiment results show that there are bainite in surface of plate,and quarter and center of plate are ferrite and pearlite for the difference of cooling rate in thickness direction.Grain size in thickness direction increases from surface to center.