弹丸膛内运动过程中弹带表层热软化机理分析

Mechanism Analysis of Thermal Softening of Rotating Band Surface in Process of Projectile Motion in Bore

为研究弹带表层金属在急剧升温条件下的热软化机理与组织演变过程,基于再结晶动力学理论分析表层金属发生再结晶及晶粒长大的可能性,研究了动态再结晶对弹带表层热软化的影响,采用金相显微镜和扫描电镜(SEM)观察并分析了回收砂弹的弹带细观与微观组织.实验中发现了存在于弹带表面薄层的再结晶组织,且部分晶粒未显著长大,这表明再结晶是弹带表层热软化的微观机理.

To study the thermal softening mechanism and structure evolution of surface metal under the sharp raise of temperature, kinetics of recrystallization was used to research the possibility of surface metal recrystallization and grains; growth. The effect of dynamic recrystallization on thermal softening of surface metal was analyzed. Mesostructure and microstructure of rotating band were observed by optical microscope and scanning electron microscopy. In experiment, recrystallization structure on surface layer of rotating band was found, and partial grains didn＇t grow remarkably. The result shows that recrystallization on surface is the microscopic mechanics of thermal softening.