The quasi-static and dynamic material properties, including the strength relation and fracture criterion, from room temperature to 250 ℃ are investigated using a universal testing machine, a torsion testing machine, a split Hopkinson tension bar and the Taylor impact test. The Johnson-Cook constitutive relation with a modification on the strain hardening term and the Johnson-Cook fracture model with a modification on the temperature softening item were proposed to fit the test results. The material constants were calibrated by a combination of experimental tests and numerical simulations. It is concluded that the strain strengthening and temperature softening effect is obvious, while the strain rate hardening effect is not significant; the fracture strain increases with temperature and strain rate and decreases with stress tri-axiality.%通过万能材料试验机、扭转试验机、霍普金森拉杆和Taylor撞击实验研究高强铝合金2A12在常温至250℃的准静态、动态本构关系和失效模型.基于实验结果,修改了Johnson-Cook 强度模型中的应变强化项以及Johnson-Cook失效模型中的温度软化项,并结合数值仿真得到了模型参数.实验结果表明,2A12铝合金的应变强化效应和温度软化效应显著,而应变率硬化效应不显著；失效应变随温度的增加、应力三轴度的减小和应变率的增加而增加.
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