Prediction of extruded microstructures using experimental and numerical modelling techniques
Prediction of extruded microstructures using experimental and numerical modelling techniques
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使用实验和数值建模技术预测挤压微观结构
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
M. Jolly
中科院分区：
文献类型：
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作者：
C. Harris;Q. Li;M. Jolly
铝是一种有价值的材料，用途不断扩大。然而，随着铝使用量的增加，对其机械和物理性能的要求也在增加。在铸造特定合金后，改变合金微观结构和性能的唯一方法是通过热机械加工。在某些情况下，挤出机需要特定的最终微观结构，以获得产品安全原因的特定机械性能，例如在结构应用中。在另一些情况下，尽管不希望出现这种结果，但微观结构几乎是加工过程中可以接受的一部分，例如，在挤压硬质合金时出现外围粗晶粒。在本研究中，研究了铝挤压过程中应变、应变速率和温度对最终挤压组织形成的影响。应变、应变率和温度本身是一个特定的挤压模具设计和过程控制的函数。研究采用工业挤压金属、实验室规模实验和整个挤压过程的有限元建模相结合的方法进行。本文将介绍目前在基础技术的发展上的发现，这些技术可以在工业中用于预测挤压产品的微观结构。最终的目标是，相同的技术可以用来指定挤压模具设计和过程控制参数，以便准确地生产所需的挤压微结构。
Aluminium is a valuable material with an ever-expanding amount of uses. However, as the use of aluminium increases so do the demands on its properties – both mechanical and physical. After the casting of a specific alloy the only method of altering the microstructure and consequently the properties of that alloy is by thermomechanical processing. In some cases extruders require a particular final microstructure in order to attain specific mechanical properties for product safety reasons, for example in structural applications. In others the resulting, although undesired, microstructure is an almost accepted part of the process, for example peripheral coarse grain in the extrusion of hard alloys. In this study, the formation of the final extruded microstructure was investigated as a function of the strains, strain rates and temperatures produced in the aluminium extrusion process. The strains, strain rates and temperatures are themselves a function of a particular extrusion die design and process control. The investigations were carried out using a combination of industrially extruded metal, laboratory scale experimentation and Finite Element Modelling of the whole extrusion process. This paper will introduce the current findings on the development of fundamental techniques that can be used within industry to predict the microstructures of extruded products. The ultimate aim is that the same techniques can then be used to specify extrusion die design and process control parameters in order to accurately produce the required extruded microstructures.