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利用自行研制的旋转盘式杆杆型冲击拉作试验装里对Fe3Al实施了不同应交率的冲击拉伸试验，获得了不同应变单下的完整的应力应变曲线．结果表明在应变率从80S-1至1200S-1范围内，Fe3Al存在明显的动态韧性现象及应变率强化效应，其屈服应力、破坏应力以及破坏应变都随应变率的提高而增加．用最小二乘法拟合得到其屈服应力、破坏应力以及失稳应变与应变率的关系，并根据Bondner-Partom的理论建立了Fe3Al冲击拉伸加载条件下的一线无屈服本构模型．SEM观察结果表明，室温下Fe3Al的断裂方式主要表现为穿晶解理断裂，影响其破坏的主要因素是氢脆（环境脆性）．观察发现，高应变率下其断口处出现明显的晶粒细化现象．高应变率抑制了空气中水汽对Fe3Al的环境腐蚀，提高了Fe3Al的变形能力，导致动态韧性．同时，还验证了H2O可加速氢脆的进程，并对上述现象进行了解释．
The impact tensile test of Fe3Al with different rate of response was carried out by using the self-developed rotary disc type rod-type impact test apparatus, and the complete stress-strain curve under different strain gauges was obtained. The results show that there are obvious dynamic ductility and strain rate strengthening effect in the range of strain rate from 80S-1 to 1200S-1, and the yield stress, failure stress and failure strain increase with the increase of strain rate. The yield stress, failure stress and the relationship between instability strain and strain rate were fitted by the least-square fitting method. According to the theory of Bondner-Partom, the first-line non-yielding constitutive model under the impact loading of Fe3Al was established. SEM observations show that the fracture mode of Fe3Al at room temperature is mainly manifested as transgranular cleavage fracture, the main factor affecting the destruction is hydrogen embrittlement (environment brittleness). It was observed that there was a clear grain refinement at the fracture site at high strain rates. The high strain rate suppresses the environmental corrosion of Fe3Al in air by water vapor, increases the deformation capacity of Fe3Al and leads to dynamic toughness. At the same time, it is also verified that H2O can accelerate the process of hydrogen embrittlement and explain the above phenomenon.