The AerMet100 ultra-high steel was cryogenic treated after quenched and then was tempered under different temperatures,the OM,SEM and TEM techniques were used to observe the micro-structure after heat treatment.The effect of different heat treatments on the dynamic mechanical properties was investigated using the split Hopkinson pressure bar.The results indicate that the con-tent of residual austenite is reduced,the dynamic plasticity is enhanced and the comprehensive proper-ties are improved after cryogenic treatment.Under high strain rate (1000-4200s-1 ),compared with the quasi static,material shows strain rate hardening effect obviously.The dynamic compression strength increases initially and then decreases with increasing tempering temperature,the peak value of about 2800MPa appears when the tempering temperature is 482℃.The material fracture form is the shear fracture when the steel is under the dynamic loading.%对 AerMet100超高强度钢淬火后深冷处理，然后在不同温度下回火，利用 OM，SEM，TEM 对处理后的组织进行观察。采用分离式 Hopkinson 压杆研究不同热处理工艺对其动态力学性能的影响规律。结果表明：深冷处理可降低残余奥氏体的含量，提高材料的动态塑性，改善材料的综合性能；在高应变率（1000～4200s－1）下，与准静态相比，材料表现出明显的应变率硬化效应。随着回火温度的升高，材料的动态压缩强度呈现出先升高后降低的趋势，在482℃时出现峰值，约为2800MPa。在动态加载条件下，材料的断裂形式均是剪切断裂。
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