高温变形条件下5A02铝合金的塑性成形性能

The plastic deformation behavior of 5A02 aluminum alloy sheet at high temperature

摘要:

随着工业技术的发展和能源问题的突出，铝合金以其质量轻、耐腐蚀性能好、成形性能和加工性能良好等优势成为轻型化首选的材料类型之一。以5A02铝合金冷轧板材为研究对象，通过单向拉伸试验和金相试验对不同变形温度、应变速率条件下5A02铝合金的塑性性能进行分析，并且借助试验数据和Zener-Hollomo参数模型，对高温条件下5A02铝合金的本构模型进行研究。研究结果表明：5A02铝合金在高温条件下变形时，应变速率和变形温度对延伸率的影响很大。在应变速率为0.01s-1、0.001 s-1、0.0005 s-1和0.0001 s-1条件下，当变形温度大于250℃时，5A02铝合金的延伸率大于100%。当变形温度为150℃~250℃时，5A02铝合金的真实应力-应变曲线属于动态回复型，而当变形温度大于250℃时，流变应力曲线存在明显的软化现象。

Abstract:

With the development of industrial technology and the rising of energy issues, aluminum alloys have become one of the preferred lightening materials for low weight, good corrosion resistance, good forming and processing properties. Taking 5A02 aluminum alloy cold-rolled sheet as the research object, the plastic deformation behavior of 5A02 aluminum alloy under different temperatures and strain rates were analyzed through uniaxial tensile test and metallographic test. Combined with experimental data and Zener-Hollomon parameter model, the constitutive model of 5A02 aluminum alloy under high temperature conditions was studied. The results show that the strain rate and deformation temperature have a great influence on the elongation when the 5A02 aluminum alloy is deformed under high temperature conditions. At strain rates of 0.01s-1, 0.001s-1, 0.0005s-1 and 0.0001s-1, the elongation of 5A02 aluminum alloy is greater than 100% when the deformation temperature is above 250°C. The true stress-strain curve of 5A02 aluminum alloy is characterized by dynamic recovery when the deformation temperature is 150°C~250°C, and the flow stress curve has obvious softening phenomenon when the deformation temperature is above 250°C.