(昆明理工大學 材料科學與工程學院 云南省新材料制備與加工重點實驗室，昆明 650093)
摘 要: 采用Gleeble-1500熱模擬試驗機研究Pb-Mg-Al合金在變形溫度453~613 K、應變速率0.01~1 s-1條件下的熱壓縮流變行為，計算應力指數(shù)和變形激活能，采用Zener-Hollomon參數(shù)法構建合金的高溫變形的本構關系，基于Murty準則，建立Pb-Mg-Al合金的加工圖。結果表明：Pb-Mg-Al合金為正應變速率敏感材料；該合金的熱壓縮變形流變應力行為可用雙曲正弦函數(shù)本構方程和Zener-Hollomon參數(shù)來描述，其平均變形激活能為149.524 4 kJ/mol；從加工圖分析并結合激活能，確定Pb-Mg-Al合金的最優(yōu)變形溫度和應變速率分別為533 K和0.1 s-1。
關鍵字: Pb-Mg-Al合金；本構關系；變形激活能；加工圖
（Key Laboratory of Advanced Materials of Yunnan Province, Faculty of Material Science and Engineering,
Kunming University of Science and Technology, Kunming 650093, China）
Abstract:The flow stress behaviors and the deformation microstructure of hot compressed Pb-Mg-Al alloy were investigated by hot compressive tests on Gleeble-1500 thermo-simulation machine in the temperature range of 453-613 K and strain rates range of 0.01-1 s-1. The stress exponent and deformation activation at elevated temperatures were calculated. The constitutive relationship of the Pb-Mg-Al alloy during hot compression deformation at high temperatures was obtained by introducing Zener-Hollomon parameter. Based on Murty criterion, the processing map for the Pb-Mg-Al alloy was obtained. The results show that Pb-Mg-Al alloy is sensitive to strain rate. The hot deformation behavior can be described by a constitutive equation in hyperbolic sine function and Zener-Hollomon parameter. The average hot deformation activation energy of Pb-Mg-Al alloy is 149.524 4 kJ/mol. The optimal processing parameters derived from processing map and activation energy are 533 K in temperature and 0.1 s-1 in strain rate.
Key words: Pb-Mg-Al alloy; constitutive relationship; deformation activation energy; processing map
