钨合金破片力学特性与爆轰驱动破碎行为的关联性

Correlation between the Mechanical Properties of Tungsten Alloy Fragments and Fracture Behavior Driven by Detonation Loading

为了研究钨合金破片样品在爆轰驱动下的破碎行为,以93W-Ni-Fe作为研究对象,对两种不同工艺得到的钨合金破片样品进行了静态压溃性能、动态力学性能和爆轰驱动破碎性实验;采用扫描电子显微镜进行金相研究,结合原始破片及爆轰加载后的回收破片微观形貌分析,实现破片在爆轰加载后的完整性预估.结果表明,在两种破片静态压溃性能相当的情况下,其动态应力应变曲线以及爆轰驱动后的破碎率也会出现明显差异,因此静态压溃性实验不足以表征破片的爆轰驱动完整率,但与动态力学性能以及金相研究结合后,发现动态应力应变曲线无明显应变硬化行为的破片更容易发生破碎,且破片微观形貌出现大量孔隙以及晶粒分布不均匀现象,说明结合动态力学性能分析可有效预估钨合金破片样品的爆轰驱动破碎行为.

To study the fracture behavior of tungsten alloy fragments driven by detonation,93W-Ni-Fe was taken as the research object and the static crushing properties,dynamic mechanical properties and fracture properties after the detonation of tungsten alloy fragments prepared by two different processes were tested.The scanning electron microscope was applied to metallographic study.Combining the original fragments and the recovered fragments after detonation loading,the integrity prediction of fragments after detonation loading was realized.The results show that the dynamic stress-strain curve and the crushing rate after detonation loading are obviously different even though the static crushing properties of the two kinds of fragments are equivalent.Therefore,the static crushing test is not enough to characterize the detonation driving integrity of fragments.However,it is found that the fragments with no obvious strain hardening behavior in dynamic stress-strain curve are more likely to be broken.Meanwhile,there are a lot of pores and uneven grain distribution in the micro morphology of fragments.The results show that the dynamic mechanical property analysis can effectively predict the detonation driven fracture behavior of tungsten alloy fragments.