火炮身管在射击过程中表层微观结构的变化

摘要

通过对比发射过1650枚炮弹和500枚炮弹的火炮身管来分析白层的形成和微观结构。白层的厚度与发射次数无关，与环境、压力、温度等条件有关。白层中确定存在奥氏体和Fe3 C，另外白层内一组更广泛的碳化物分别是Fe2 C， Fe5 C2和Fe20 C9。共晶体和碳化物的形成说明是液相冷却的结果，暗示氧化过程发生的同时产生渗碳，可推导出白层形成和磨损侵蚀率之间的关系。%The white-layer formation and its microstructure are investigated in two fired gun barrels, one after 1650 rounds and the other after 500 rounds.The thickness of the white layer is independent of the number of rounds fired,and it is probably a function of the environment, pressure and temperature conditions.The presence of austenite and Fe3C in the white layer is confirmed, but in addition a much wider spectrum of carbides is observed within the white layer, namely Fe2C, Fe5C and Fe20C9.The morphology of the eutectic and carbides is a result of splat cooling from the liquid state.It is indicated that the oxidizing process takes place concurrently with carburization .Some correlations between the white-layer formation and the wear erosion rate could be deduced .