粉末压制Al-W合金热变形行为与涡旋动盘成形研究

发布时间：2018-06-01 04:24

  本文选题：Al-W合金 + 本构方程　； 参考：《中北大学》2015年硕士论文

【摘要】：近年来,汽车工业的发展非常迅速,已经成为了我国的支柱产业,为了达到汽车轻量化的目标,铝合金作为一种新的轻合金被广泛地应用到了汽车制造中。随着人们的生活水平的提高,对汽车的安全性和舒适度等又提出了新的要求。汽车空调是保证汽车舒适的重要零部件,而涡旋盘属于汽车空调制冷压缩机的核心零部件,对汽车空调的性能有着极其重要的影响,尤其是耐磨性,跟汽车的安全性能密切相关,故针对涡旋盘的材料和成形工艺的研究得到越来越多的重视。传统的涡旋盘成形采用的是普通铝合金,本文采用了一种新型的Al-W粉末材料,并针对该材料提出了新的粉末成形方法,以克服传统粉末冶金构件局部密度超差、产品结构形状有一定限制的缺点,并提高零件的耐磨性。 本文研究的原材料是机械合金化得到的Al-W粉末,随着通过粉末压制的方法得到Al-W合金热压坯,将其作为涡旋盘的零件毛坯,然后对热压坯料进行了热压缩试验,对Al-W合金的热变形力学行为进行了研究。通过回归分析的方法,分析了热变形过程中Al-W合金的流变应力σ、应变速率ε及变形温度T之间的相关性,并建立了Al-W合金的应变补偿型Arrhenius本构方程,为数值模拟工作提供必要的材料模型和参数,得到的本构模型如下： 以材料动态模型为基础,绘制出Al-W合金的加工图,并对其加以分析,最后确定了Al-W合金最佳的安全加工区域为：温度560℃-570℃,应变速率为0.01s-1-0.001s-,此时,其功率耗散因子达到最大值0.55,为Al-W合金的工艺制定提供了实验参数。 利用DEFORM-3D软件对Al-W合金涡旋动盘背压成形进行了数值模拟,分析了成形过程中材料的流动规律,并对模具圆角半径大小对成形力、等效应力分布规律的影响进行了分析,为涡旋动盘的工艺制定和模具设计提供了合理的依据,得到的结论为：随着圆角半径的增大,成形力有所减小。圆角半径越大,涡旋体部位的等效应力分布越均匀,变形越均匀,最终确定合适的圆角半径应为2.5。最后对涡旋动盘零件进行了实验试制，对有限元模拟结果的准确性进行验证。
[Abstract]:In recent years, the automobile industry has developed very rapidly and has become the pillar industry of our country. In order to achieve the goal of automobile lightweight, aluminum alloy has been widely used in automobile manufacturing as a new light alloy. With the improvement of people's living standard, new requirements are put forward for the safety and comfort of automobiles. Automobile air conditioning is an important part to ensure automobile comfort, and scroll disc is the core part of automobile air conditioning refrigeration compressor, which has an extremely important influence on the performance of automobile air conditioning, especially the wear resistance. It is closely related to the safety performance of automobile, so more and more attention has been paid to the material and forming process of vortex disc. Conventional aluminum alloy is used in the traditional vortex disk forming. A new Al-W powder material is used in this paper, and a new powder forming method is put forward to overcome the local overdensity difference of the traditional powder metallurgy component. The structure of the product has some limitations on the shape of the defects and improve the wear resistance of the parts. The raw material studied in this paper is the Al-W powder obtained by mechanical alloying. With the method of powder compaction, the hot pressed billet of Al-W alloy is obtained, which is used as part blank of vortex disk, and then the hot compression test of hot pressed blank is carried out. The thermal deformation mechanical behavior of Al-W alloy was studied. The correlation between flow stress 蟽, strain rate 蔚 and deformation temperature T of Al-W alloy during hot deformation was analyzed by regression analysis, and the strain compensated Arrhenius constitutive equation of Al-W alloy was established. The necessary material models and parameters are provided for the numerical simulation work. The constitutive models are obtained as follows: Based on the material dynamic model, the machining diagram of Al-W alloy was drawn and analyzed. Finally, the optimum safe processing area of Al-W alloy was determined as follows: temperature 560 鈩，

本文编号：1962827