Mechanical properties and constitutive equation of pressed CL−20 based aluminized explosives

Abstract

To investigate the mechanical properties and constitutive equation of pressed CL−20 based aluminized explosives, the stress-strain curves at different strain rates are obtained by quasi-static and dynamic compression tests using universal testing machine and Split Hopkinson Pressure Bars (SHPB), respectively. The results suggest that the quasi-static and dynamic compression process of pressed CL−20 based aluminized explosives can be divided into elastic stage, hardening stage, and strain soften. In the process quasi-static compression, the pressed CL−20 based aluminized explosives have obvious strain rate effects. As the strain rate increases, the elastic modulus and ultimate strength increase, while the critical strain decrease, and the elastic stress basically remains unchanged. Under dynamic compression, strain rate effects are not obvious in the initial stage when the strain is less than 0.01. When the strain is larger than 0.01, there is a significant strain rate effects, causing the elastic stress, elastic modulus and ultimate strength to increase as dynamic loading strain rate increasing. In addition, the constitutive equations under quasi-static and dynamic compression are described by power-exponential hardening model and ZWT model, and the test results of which are in good agreement with the model calculations, indicating that the two model can be used to describe the mechanical properties of a pressed CL−20 based aluminized explosives.