大规格NM450钢板喷水淬火有限元模拟

Finite element simulation of water jet quenching for large NM450 steel plate

采用材料科学计算软件Jmatpro计算了NM450耐磨钢在不同温度下的材料性能参数;通过建立60 mm厚NM450钢板的热处理物理模型和数学模型,模拟分析了钢板在喷水冷却过程中的温度场、组织场以及应力场和硬度场的变化规律,并进行了相应的试验验证。结果表明：冷却初期,钢板内外温差较大,表面受到拉应力作用,心部受到压应力作用;随着冷却时间的延长,钢板内外温差逐渐变小,表面向压应力转变,心部向拉应力转变;淬火完成后,表面组织为马氏体、心部为59%贝氏体和40%马氏体,硬度由表面的487 HBW往心部的423 HBW逐渐过渡降低。

The material performance parameters of NM450 wear resistant steel at different temperatures were calculated by the material scientific calculation software Jmatpro.By establishing the physical model and mathematical model of heat treatment for 60 mm thick NM450 steel plate,the variation law of temperature field,structural field,stress field and hardness field during the spray cooling process wss simulated and analyzed,and the corresponding experimental verification was carried out.The results show that at the beginning of cooling,the temperature difference between inside and outside of the steel plate is larger,the surface is subjected to tensile stress,and the central of the plate is subjected to pressure stress.With the cooling time prolonging,the temperature difference between the inside and outside of the steel plate becomes smaller,and the transition from compressive stress to tensile stress on the surface,but the changge of the central of the plate is just contray to it.After the quenching is completed,The surface of the plate is composed of martensitic structure,and 59% bainite and 40% martensite in the central of the plate,and the hardness of the surface is gradually reduced from the 487 HBW of the surface to the423 HBW of the central of the plate.