Mechanical Properties and Failure Criteria of DNP-based Melt-cast Explosives
3,4-dinitropyrazole (DNP)-based melt-cast explosive,characterized by its high energy content and enhanced safety,holds significant promise for applications in the field of energetic materials. Research into the mechanical properties and failure modes of this explosive under various stress conditions will provide essential theoretical and experimental support for its engineering applications. In this study,the quasi-static compressive mechanical properties,dynamic compressive mechanical properties,and quasi-static tensile mechanical properties of DNP-based melt-cast explosives are test using Instron 5965 universal materials testing machine and a split Hopkinson pressure bar. The influences of factors such as the content of additive ( cellulose acetate butyrate ) and strain rate on the mechanical properties are analyzed. The failure modes of DNP-based melt-cast explosives under quasi-static compression,dynamic compression,and quasi-static Brazilian splitting conditions are studied. The results demonstrate that the compressive strength of DNP-based melt-cast explosives generally increases with an increase in strain rate. The compressive strength decreases with an increase in the content of the additive under quasi-static loading,while it increases with an increase in the content of the additive underdynamic loading. A significant improvement in the tensile strength of melt-cast explosives is observed when the content of the additive reaches a certain threshold. Furthermore,the applicable strength failure criteria for DNP-based melt-cast explosives differ under different loading conditions,the quasi-static compression follows the maximum shear stress criterion,the dynamic compression adheres to the maximum tensile strain criterion,and the Brazilian disc test conforms to the maximum tensile stress criterion.