基于数值模拟的铸钢基体堆焊锻模焊层厚度优化  

Numerical Simulation-Based Optimization of Welding Thickness of Forging Die Manufactured by Steel Casting Surfacing

作　　者：卢顺[1] 周杰[1] 曾强[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400044

出　　处：《华南理工大学学报（自然科学版）》2014年第3期84-89,124,共7页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金面上项目(51275543);科技部重大专项(2012ZX04010-081)

摘　　要：为解决目前模具制造业中遇到的高成本、低寿命等问题,文中提出了一种基于铸钢基体的表面堆焊制备锻模的方法.针对其中焊接厚度的控制难题,将试验验证与计算机有限元数值分析相结合,建立了基于ZG310-570基体表面堆焊模具的有限元简化模型,采用热循环曲线法模拟铸钢基体模具表面堆焊及回火去应力过程,并分析温度场和不同焊接层厚度的残余应力场分布.结果表明:有限元数值分析能较好地模拟实际铸钢基体表面堆焊锻模的制备过程;基体近焊缝位置等效应力随焊接厚度的增加而降低,到焊层厚度为15 mm后趋于平稳;远离焊缝位置的残余应力随焊接厚度增加而逐渐升高,焊道对基体部位的影响也随之增大,使得铸钢基体材料在使用过程中出现缺陷的可能性显著增加.综合考虑焊接厚度对铸钢基体的影响及模具制造成本等因素,认定该工艺条件下铸钢基体表面堆焊层的最优厚度为15mm.In order to solve the problems of high cost and short life span in current die manufacturing,a method to manufacture forging die via steel casting surfacing is proposed. In view of the control of welding thickness,with thermal cycle curve method,the welding and tempering process is simulated on a simplified finite element model of the ZG310-570 surfacing die by means of finite element analysis and experimental verification,and the temperature field and the residual stress field varying with welding thickness are analyzed. The results show that （1）finite element analysis is effective in simulating the manufacturing process of forging die;（2 ）the equivalent stress near the welding joint decreases as the welding thickness increases until the latter reaches 15 mm;（3 ）the residual stress far away from the welding joint increases with the welding thickness,and the impact of weld bead on the substrate subsequently strengthens,and thus the possibility of defect of steel casting material in use increases significantly. When we take into account such factors as the influence of welding thickness on cast-steel substrate and the manufacturing cost,15 mm should be regarded as the optimal welding thickness of the surface layer of steel casting.

关 键 词：铸钢 焊接厚度 焊接应力 数值模拟 

分 类 号：TG47[金属学及工艺—焊接]