Mesoscopic Shock Phenomena of Cell Structures

本研究的目的是了解凝聚态物质中的介观尺度激波现象，凝聚态物质具有由各种小缺陷、裂纹和不均匀组成的胞状结构。我们进行了以下实验和分析研究：[1]铝蜂窝和巴拉萨木材在冲击载荷作用下的弹塑性变形和断裂。[2)冲击波在磁场中的传播。[3)固体相二氧化碳在高速冲击压缩下的冲击特性。[4)材料在极低温度下受到高速冲击的脆性断裂。在冲击实验中，我们使用了Hopkinson压杆、一级气枪、二级轻气炮和激波管。用应力计和质点速度计测量了弹塑性变形过程和应力波的传播。用光学显微镜和扫描电子显微镜观察了受冲击和未受冲击的材料，发现了由于材料中包含的细胞结构和不均匀而产生的各种有趣的冲击现象。

Objective of this research is to understand mesoscopic scale shock phenomena in condensed matter which have cell structures consisting of various kinds of small defects, cracks and inhomogeneities. We conducted the following experimental and analytical studies :[1] Elastic and Plastic deformations and fractures of aluminum honeycombs and balasa woods subjected to impact loads.[2] Shock wave propagation in magnetic fluid in magentic field.[3] Shock properties of solid phase CO2 under high-speed shock compression.[4] Brittle fracture of materials subjected to very high-speed impact at very low temperature.In shock experiments, we used a Hopkinson pressure bar, a one-stage gas gun, a two-stage light-gas gun, and a shock tube. Elastic and plastic deformation process and stress wave propagation were measured using stress gauges and particle velocity gauges. Shocked and unshocked materials were inspected using an optical microscope and a SEM.We found various interesting shock phenomena due to cell structures and inhomogeneities included in materials.