铸造中碳钢钢锭凝固组织的数值模拟  

Numerical Simulation Study on Solidification Microstructure of Cast Steel Ingot

作　　者：李吉林[1] 伍伟 冯俊宁 LI Ji-in;WU Wei;FENG Jun-ning(School of Materials Science and Engineering,North Minzu University,Yinchuan 750021,Ningxia,China)

机构地区：[1]北方民族大学材料学院,宁夏银川750021

出　　处：《铸造》2024年第7期1010-1016,共7页Foundry

基　　金：北方民族大学中央高校基本科研业务费专项资金(2022XYZCL01)。

摘　　要：使用CAFE方法模拟了铸造中碳钢钢锭的凝固组织,确定了适用于砂型铸造中碳钢钢锭凝固组织数值模拟的相关参数,主要包括形核密度(n)、形核过冷度(ΔT)及枝晶尖端生长动力学参数(a2,a3)。在此基础上,对比分析了形核和长大过程参数对数值模拟结果的影响,发现在面形核过冷度(ΔT_(s,max))不变的情况下,提高体形核过冷度(ΔT_(b,max))会显著增加钢锭组织中柱状晶的比例;在形核参数不变的前提下,增大a2和a3,也会显著扩大柱状晶区的面积;对不同冷却条件下的钢锭凝固组织的数值模拟结果表明,随着冷却速度的加快,钢锭组织中柱状晶的数量明显增加。The solidification microstructures of a cast medium carbon steel ingot were simulated using the CAFE method,and relevant parameters including the nucleation density(n),the nucleation undercooling(ΔT)and the dendrite tip growth kinetics parameters(a2,a3),which suitable for the numerical simulation of the soidification microstructure of sand-casting medium carbon steel ingot,were determined.On this basis,the influnces of different nucleation and growth parameter conditions on the numerical simulation results were compared and analyzed.It was observed that when the surface nucleation undercooling(ΔT_(s,max))was kept constant,the columnar crystal region expanded as the bulk nucleation undercooling(ΔT_(b,max))increased;when the nucleation parameter conditions were kept constant,increasing the values of a2 and a3 also led to an expansion of the columnar crystal region;the numerical simulation results of the solidification microstructures of the cast steel ingots under the conditions of different cooling rates showed that the quantities of the columnar crystals increased as the cooling rate was increased.

关 键 词：凝固组织 数值模拟 晶粒形核 枝晶长大 

分 类 号：TG26[金属学及工艺—铸造]