Effect of flow stress calculation on formability of aluminum alloy warm sheet hydroforming

被引：0
|
作者：
Cai G. [1 ,2 ]
Wu C. [1 ]
Lang L. [3 ]
Gao Z. [2 ]
机构：
[1] Faculty of Mechanical Engineering & Automation, Zhejiang Sci-Tech University, Hangzhou
[2] Ningbo XingJian Space Machinery Co., Ltd., Ningbo
[3] School of Mechanical Engineering and Automation, Beijing University of Aeronautics and Astronautics, Beijing
来源：
Beijing Hangkong Hangtian Daxue Xuebao/Journal of Beijing University of Aeronautics and Astronautics | 2018年 / 44卷 / 10期
关键词：
Flow stress; Formability; Pressure rate; Stress-strain curve; Warm sheet hydroforming;
D O I：
10.13700/j.bh.1001-5965.2018.0025
中图分类号：
学科分类号：
摘要：
In order to research the influence of flow stress calculation on formability of aluminum alloy warm sheet hydroforming, warm sheet bulging test was carried out to obtain bulging height-pressure curves with different bulging diameters in this study. Based on the data of bulging parts profile measured by three coordinate measuring machine, the least square circle fit (LSCF) radius were fitted, and it was found that when the height-diameter ratio h/a was in the range of 0.18<h/a≤0.68, the corresponding value of roundness error between the radius of curvature and the circle radius was 5%. By comparing the existing theoretical models for radius of curvature and thickness, which is combined with flow stress calculation, it was found that the average value of radius of curvature model Hill and Panknin, and the thickness model Kruglov-Hill are in the most accordance with experimental data. The combination model was used to calculate the bulging height-pressure curves obtained by bulging test, and then the stress-strain curves with different temperatures and pressure rates were obtained. It was found that there was a little impact on radius of curvature for different directions (rolling direction and vertical direction) of the bulging parts formed with 7075-O aluminum alloy at 210℃, while the pressure rate can affect the stress-strain curves. © 2018, Editorial Board of JBUAA. All right reserved.
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页码：2035 / 2042
页数：7
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