Experimental and analytical investigations of extrusion seams in magnesium hollow profiles

镁空心型材挤压缝的实验和分析研究

• 批准号: 232117021
• 负责人: Privatdozent Dr.-Ing. Sören Müller
• 金额: --
• 依托单位: Zentraleinrichtung Elektronenmikroskopie (ZELMI)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/232117021?language=en
• 关键词: Experimental; analytical; investigations; extrusion; seams

The extrusion of hollow profiles is predominantly done with porthole dies. At the bridges in the prechambers of the die the billet material is divided into two or more separate material flows. Before the material leaves the die through the die recess the material is joined together in the welding chamber. The material separation and later on the welding cause extrusion seams in the extrusion direction in the profiles. If the extrusion is done billet-on-billet additional cross-seams occur. The formation of the extrusion seams is very important for the quality of the extruded products.Whereas the extrusion of hollow profiles with porthole dies is well known for aluminum alloys, there are almost no research regarding the extrusion of magnesium hollow profiles. Due to the lack of essential scientific findings about the formation of extrusion seams in magnesium hollow profiles, about the microstructural characteristics of the extrusion seam and the effect on the mechanical properties a fundamental research is necessary. Therefore the project includes a broad characterization of the microstructure and the mechanical properties oh the extrusion seams in dependence of the extrusion parameters. Furthermore, in order to optimize the extrusion of magnesium hollow profiles accompanying FE-simulations will be carried out.

空心型材的挤压主要使用分流模来完成。在模具预燃室中的桥处，坯料被分成两个或更多个单独的材料流。在材料通过模具凹口离开模具之前，材料在焊接室中接合在一起。材料分离和随后的焊接会在型材的挤压方向上产生挤压缝。如果挤压是在坯料上进行的，则会出现额外的交叉接缝。挤压缝的形成对于挤压产品的质量非常重要。虽然用分流模挤压空心型材对于铝合金来说是众所周知的，但是对于镁空心型材的挤压却几乎没有研究。由于缺乏关于镁空心型材挤压缝形成的重要科学发现，因此有必要对挤压缝的微观结构特征及其对机械性能的影响进行基础研究。因此，该项目包括根据挤压参数对挤压接缝的微观结构和机械性能进行广泛的表征。此外，为了优化镁空心型材的挤压，将进行有限元模拟。