塑性变形中锻件内部孔洞缺陷闭合规律的仿真模拟研究  

Simulation Study on the Closing Law of Internal Hole Defects in Forgingsduring Plastic Deformation

作　　者：黄涛 徐超 张惠惠 谢军 于梦圆 姜文学 HUANG Tao;XU Chao;ZHANG Huihui;XIE Jun;YU Mengyuan;JIANG Wenxue

机构地区：[1]二重(德阳)重型装备有限公司,四川德阳618000 [2]中国联合重型燃气轮机技术有限公司,北京100016

出　　处：《大型铸锻件》2024年第5期60-64,共5页Heavy Casting and Forging

摘　　要：采用有限元数值模拟方法,研究了锻件在塑性变形过程中,三向压应力和模具压下速度对等效应变及孔洞在物理闭合前形态变化的影响,通过对比预设的内部球形孔洞体积、长轴和短轴的变化情况,揭示了其物理闭合规律。研究发现:塑性变形中预设孔洞周围等效应变明显大于本体其它位置;变形率相同时,较大的三向压应力和较小的压下速度更有利于工件内部孔洞的闭合,长轴长度的快速减小标志着孔洞开始物理闭合,孔洞的物理闭合方向与上模压下方向一致。By means of finite element numerical simulation,the effect of three-way compressive stress and screwdown speed of die on the equivalent strain and the morphologic change of the hole before physical closure during plastic deformation of the forging were studied.The physical closure law was revealed by comparing the changes of the volume,long axis and short axis of the spherical hole in the preset interior.It is found that the equivalent strain around the preset hole during plastic deformation is obviously greater than that at other positions of the body.In case of the same deformation rate,the larger three-way compressive stress and the smaller screwdown speed are more conducive to the closure of the internal holes of the forge piece.The rapid reduction of the length of the long axis indicates the start of physical closing of the holes.The physical closing direction of the holes is consistent with the screwdown direction of the top die.

关 键 词：物理闭合 孔洞缺陷 塑性变形 应力集中 

分 类 号：TG316[金属学及工艺—金属压力加工]