基于数值分析的汽车六角锁紧螺母冷镦工艺改进  

Improvement on cold heading process for automobile hexagon lock nut based on numerical analysis

作　　者：赵庆雨 杨嵩 Zhao Qingyu;Yang Song(Department of Mechanical Engineering,Langfang Technician School,Langfang 065000,China;Industrial Technology Center,North China Institute of Aerospace Engineering,Langfang 065000,China)

机构地区：[1]河北省廊坊技师学院机械工程系,河北廊坊065000 [2]北华航天工业学院工业技术中心,河北廊坊065000

出　　处：《锻压技术》2022年第10期29-35,共7页Forging & Stamping Technology

基　　金：河北省重点研发科技计划项目(18211840)。

摘　　要：某型号车用六角锁紧螺母采用6工位冷镦加工成形,但其薄壁特征需后续采用车加工成形,不仅降低了生产效率、增加了成本,对螺母的性能也有一定的影响。针对该问题,提出了一种六角锁紧螺母6工位冷镦新工艺,在冷镦过程中同时成形薄壁特征。采用有限元数值模拟软件Deform-3D对改进后方案各工位的零件成形过程进行了分析,建立了45钢的本构模型和断裂模型;并从零件的成形外观、内部网格流线图以及损伤值分布情况等方面分析了零件的成形质量,通过各工位的载荷情况分析了各工位模具寿命的差距。研究结果表明:采用改进后方案,能够成形出外形饱满、满足尺寸要求、内部无缺陷的六角锁紧螺母,同时各工位的模具寿命接近,利于全体换模。经多工位冷镦试验获得的六角锁紧螺母的质量较好,尺寸满足要求,验证了新工艺的可行性,对同类零件的工艺开发起到了一定的指导作用。A certain type of automobile hexagon lock nut is formed by six-station cold heading,but its thin-walled feature needs to be formed by subsequent turning,which not only reduces the production efficiency,increases cost,but also has a certain influence on the nut performance.Therefore,in order to solve this problem,a new six-station cold heading process for hexagon lock nut was proposed,and the thin-walled feature during the cold heading process was formed simultaneously.Then,the forming process of part at each station in the improved scheme was analyzed by finite element numerical simulation software Deform-3 D,and the constitutive model and the fracture model of 45 steel were established.Furthermore,the forming quality of part was analyzed from the aspects of forming appearance,internal grid streamline diagram and damage value distribution condition,and the difference of mold life for each station was analyzed by the load condition of each station.The results show that the improved scheme can form the hexagonal lock nut with a full shape which meets the size requirement and has no internal defects,and at the same time,the mold life of each station is close which is beneficial to the overall mold replacement.The quality of hexagon lock nut obtained by the multi-station cold heading test is good,and the size meets the requirement,which verifies the feasibility of the new process and plays a certain guiding role in the process development of similar parts.

关 键 词：六角锁紧螺母 冷镦工艺 本构模型 断裂模型 损伤值 模具寿命 

分 类 号：TG386.3[金属学及工艺—金属压力加工]