Quasi-static and dynamic mechanical characterization of clay and ballistic soap

Abstract

Ballistic gelatin, soap, and clay are three human simulated target materials commonly used in the field of wound ballistics research. Currently, there are more studies on ballistic gelatin’s mechanical properties, but rarely on clay and soap. In this paper, the mechanical properties of clay and soap materials were tested by using universal material testing machine and Hopkinson bar, respectively, and their stress-strain curves were obtained under different temperatures (4°C, 15°C, and 25°C) from quasi-static to dynamic loading. The test results showed that the clay material was sensitive to temperature and strain rate in quasi-static conditions, its stress-strain curves showed nonlinear strengthening characteristics, and the stress always increased without strength decrease during the loading process; the dynamic compression mechanical properties of clay were significantly higher than the quasi-static mechanical properties, showing obvious strain rate strengthening effect. In quasi-static compression experiments, the stress-strain curves of soap material showed bilinear elastic-plastic material characteristics; when the strain was less than 0.1, it was insensitive to temperature and strain rate, and only when the strain was more significant than 0.1 did it show a certain temperature and strain rate correlation. The dynamic compressive mechanical properties of soap are significantly higher than the quasi-static mechanical properties, showing a significant strain-rate strengthening effect. The stress of soap at the same strain rate is slightly less than that of clay. These results not only help provide more accurate material parameters for relevant numerical calculations but also help to provide references for the development of new bionic materials.