Phase-Field Modelling of the Solidified Nodular Cast-Iron Alloy EN–JS2070 Micro Structure for Deep Drawing Tool Application Treated by Machine Hammer Peening
Phase-Field Modelling of the Solidified Nodular Cast-Iron Alloy EN–JS2070 Micro Structure for Deep Drawing Tool Application Treated by Machine Hammer Peening
复制标题
用于经机锤喷丸处理的深拉工具应用的凝固球墨铸铁合金 ENâJS2070 微观结构的相场建模
DOI：
10.1007/978-3-030-03451-1_33
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Klocke
中科院分区：
文献类型：
--
作者：
Mannens;Trauth;Kittel;Klocke
先进高强度钢（AHSS）作为车身部件材料的使用量不断增加，导致汽车重量不断减轻，从而降低了二氧化碳排放量。与传统钢种相比，AHSS的屈服强度和抗拉强度更高，因此重量减轻。然而，AHSS的较高强度也导致成形工具上的较高载荷。为了提高刀具表面的耐磨性，使用机械表面处理。球墨铸铁合金EN-JS 2070经机锤喷丸处理后，表面出现细小缺陷。最近的研究表明，破碎的石墨，从而崩溃的缩孔是这些表面缺陷的发生的原因，为了减少在铸造工具中的缺陷的数量，采用冷却模具的冷却程序。采用不同的工艺参数对冷却模生产的EN-JS 2070铸造合金拉深工具进行了MHP处理。为了分析所采用的冷却程序对石墨形成以及随后对MHP之后的缺陷起源的影响，借助于MICRESS®软件执行基于相场法的凝固过程模拟。一个传统的凝固过程和冷却模具的过程被认为是石墨分数，尺寸和局部化方面的最终显微组织进行了分析。对EN-JS 2070模具进行了冷却结晶凝固的金相分析，并与无冷却结晶凝固的模具进行了比较。与开发的相场模型预测冷却后的最终组织是在良好的协议与光学显微镜观察所揭示的组织。从相场模拟结合金相分析的数据得到的结果被用来改善MHP后的表面缺陷的发生负责的缺陷形成的解释模型，以及调查所使用的冷却策略。
The increased usage of advanced high strength steels (AHSS) as materials for car body parts leads to a continuous reduction of car weight and thus a lowering of CO2emissions. This weight reduction results from the higher yield and tensile strength of AHSS when compared to conventional steel grades. However, the higher strength of AHSS also leads to higher loads on the forming tools. To increase the wear resistance of tool surfaces, mechanical surface treatments are used. Small surface defects were observed after machine hammer peening (MHP) of nodular cast-iron alloy EN-JS2070. Recent investigations identified that disintegrated graphite and thus collapsing shrink holes are the cause for the occurrence of these surface defects.In order to reduce the amount of defects in the cast tool, an adopted cooling procedure with a cooling mould was employed. The deep drawing tools from EN-JS2070 cast alloy produced with cooling mould were treated with MHP using varying process parameters. In order to analyse the influence of the adopted cooling procedure on graphite formation and subsequently on defect origination after MHP, a phase-field method based simulation of the solidification process by means of MICRESS®software is performed. A conventional solidification process and a process with cooling mould are considered and a final microstructure in terms of graphite fraction, size, and localisation is analysed. The metallographical investigations of the EN-JS2070 cast tool solidified with cooling mould were performed and subsequently compared with those of casting without cooling mould. The final microstructure after cooling predicted with the developed phase-field model is in good agreement with the microstructure revealed by light-microscope observations. The findings obtained from the phase-field simulation combined with the data from metallographical analysis are used to improve the explanation model of the defect formation responsible for the occurrence of surface defects after MHP as well as to investigate the used cooling strategy.
汽车用工业铸造工具机锤喷丸后的表面缺陷分析
DOI：
10.1016/j.proeng.2017.10.1139
发表时间：
2017
期刊：
Procedia Engineering
影响因子：
--
作者：
Mannens;Delforno;Trauth;Feuerhack;Kittel;Klocke
通讯作者：
Klocke