13MnNiMoR钢板热冲压成型封头的冲击性能存在不合格现象。采用化学成分分析、力学性能测试、金相检验及模拟热处理等方法，对13MnNiMoR钢封头冲击韧度显著降低的原因进行了分析。结果表明：对于较厚的封头，正火处理后的冷却速率严重不足，致使碳化物沿铁素体晶界析出，且在高温回火过程中碳化物再次长大；在冲击过程中，封头在外力作用下容易在碳化物析出位置发生断裂，导致封头的冲击韧度显著降低至不合格。

The impact toughness of hot-pressed 13MnNiMoR steel vessel heads was unqualified. By means of chemical composition analysis, mechanical property testing, metallographic examination, simulated heat treatment and so on, the significant decrease reasons of impact toughness of the hot-pressed 13MnNiMoR steel vessel heads were analyzed. The results show that:the cooling speed of thick vessel heads after normalization treatment was seriously insufficient, which led to the carbide precipitation along the ferrite grain boundaries, and then carbide grew up in the process of high-temperature tempering process; in the impact process, the vessel heads were easy to fracture at the position of carbide precipitation under the exogenic action, leading to the significant decrease and disqualification of impact toughness of the vessel heads.