SCM435合金钢接头的冷镦工艺研究与数值模拟

Research and numerical simulation on cold heading process of SCM435 alloy steel joint

某规格的SCM435合金钢接头采用“热镦+铣槽”的生产方式,工序复杂、生产效率低、产品质量不稳定,针对该问题,提出了产品质量更稳定、适合批量化加工的多工位冷镦成形工艺。基于单向拉伸试验,通过Deform-3D有限元软件建立了SCM435合金钢材料的本构关系和临界损伤模型,并对合金钢接头各工位的连续冷镦成形过程进行了动态模拟,从金属流动规律、成形饱满度、成形载荷变化以及损伤值分析等角度来预判潜在的缺陷,从而验证工艺的可行性。研究结果表明:针对该合金钢接头制定的6工位冷镦工艺方案切实可行,各工位零件成形良好,无折叠、开裂缺陷,金属流动合理,成形载荷分布均匀,最大损伤值均小于材料的损伤阈值。最后通过多工位冷镦机进行了试生产,获得了符合要求的合金钢接头。

A SCM435 alloy steel joint adopts the production mode of “hot upsetting + slot milling”, which has complicated process, low production efficiency and unstable product quality. In view of this problem, a multi-station cold heading process with more stable product quality and suitable for batch processing was proposed to replace it. Based on the uniaxial tensile test, the constitutive relationship and critical damage model of SCM435 alloy steel were established by finite element software Deform-3 D, and the continuous cold heading process of each station for alloy steel joint was dynamically simulated. Then, the potential defects were predicted from the perspectives of metal flow law, forming plumpness, forming load change and damage value analysis, and the feasibility of the process was verified. The results show that the six-station cold heading process scheme for the alloy steel joint is feasible, the parts in each station are well formed without folding and cracking defects, the metal flow is reasonable, the forming load distribution is uniform, and the maximum damage value is less than the damage threshold of the material. Finally, the trial production is conducted by the multi-station cold heading machine, and the alloy steel joint that meets the requirements is obtained.