为了解不同温度条件下粒状发射药动态力学性能的变化，用落锤撞击试验研究了粒状发射药在－60～50℃下的撞击损伤状态及应力曲线的变化。结果表明，在不同温度条件下粒状发射药的落锤撞击损伤状态和应力曲线的变化很大，温度低于－20℃时，发射药可能发生破碎，应力峰值高、作用时间短，温度高于0℃时，发射药发生塑性形变、峰值低、作用时间长。认为随着温度的逐渐升高，粒状发射药由脆性断裂逐渐改为塑性变形，药粒不易破碎，而低温下的冷脆断裂对发射药在极端低温下的应用不利。%To understand the change of dynamic mechanical properties of granular gun propellant under different temperatures,the impact damage state and change in stress curve of gun propellant under temperature of -60-50℃were studied by a drop hammer impact test.Results show that the impact damage state and change in stress curve of gun propellant under different temperatures are very different.When the temperature is lower than -20℃,gun propellant may be broken with high stress peak value and short stress action time.When the temperature is higher than 0℃,the propellant occurs plastic deformation,the stress peak value is low and the stress action time is long. Considering that with the increase of temperature,granular gun propellant gradually changes from brittle fracture to plastic deformation and is not easy to be broken,whereas the cold friable fracture at lower temperature is adverse for the application of gun propellant under the extreme environments.
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