Open Access Open Access  Restricted Access Subscription or Fee Access

Evaluation of the Dynamic Fracture Characteristics (Plasticity) of Shaped Charge Jets at Different Strain Rates and Characterized Initial Liner Microstructure

F. MAJIET, F. J. MOSTERT

Abstract


The breakup phenomenon in shaped charge jets have been studied for numerous designs over many decades. The main focus of this research was to demonstrate the influence of varying strain, strain rate behaviour on shaped charge jet break up times with copper liners which have fixed grain sizes/microstructures. The overall strain and strain rate was varied by changing shaped charge liner angle and by using different initiation systems. Two liner designs 60⁰ and 120⁰ (full angle, respectively) were evaluated with comparable microstructures. The strain and strain rate of shaped charge jets was further modified with two initiation systems (point initiation and peripheral initiation). ANSYS AutodynTM simulation software was used to model the various shaped charge designs to allow a strain, strain rate variance by varying the jet tip and tail velocities. Double flash x-ray analysis was conducted on all shaped charge warhead designs and then analysed with image detection software to obtain the jet parameters to a high degree of accuracy. The cumulative length, breakup times, velocity difference, tip and tail velocities were calculated for each design. These parameters were used to evaluate a “dynamic fracture parameter” (or plasticity indicator) for the various designs. It was found that this parameter was constant for all the designs if it is evaluated from jet tip to a particular jet velocity.


DOI
10.12783/ballistics2019/33256

Full Text:

PDF

Refbacks

  • There are currently no refbacks.