Title
Dynamic material characterization by combining ballistic testing and an engineering model
Author
Carton, E.P.
Roebroeks, G.H.J.J.
van der Wal, R.
Publication year
2013
Abstract
At TNO several energy-based engineering models have been created for various failure mechanism occurring in ballistic testing of materials, like ductile hole growth, denting, plugging, etc. Such models are also under development for ceramic and fiberbased materials (fabrics). As the models are energy-based they can be directly compared to experimental results of ballistic tests as the mass and velocities of projectiles are regularly measured. This allows the models to be validated, as has been done for the ductile hole growth model. Using AP-rounds on ductile target materials like many metals, clay and polymers, ductile hole growth (DHG) normally is the major failure mechanism during projectile penetration. When the core of the projectile remains rigid (which is often the case in ductile materials) the loss in kinetic energy of the core is easily measured from its initial and residual velocity. In the DHG-engineering model this energy loss is also calculated but requires that the flow stress at high strain rates is known. Using the experimental results in combination with this engineering model the dynamic flow stress of the target has been quantified. This procedure has been done for several material (metals, clay types and polymers) and allows the determination of dynamic material properties that are otherwise not easily measured. This method requires a rigid penetration of a projectile through a (thick) plate of the material to be characterized. Hence, no special sample shape or dimension is required. The dynamic flow stresses that are obtained have been compared to high strain rate (order 1000/s) strength values of the same materials determined by other techniques. As the values are very close to each other, this provides confidence in the approach to use ballistic test results of targets failed by DHG in combination with the engineering model for the characterization of materials at high strain rates.
Subject
Armor
Light-weight armour
Dynamic material properties
Characterization
Ballistic tests
Engineering modeling
Defence Research
Defence, Safety and Security
Mechatronics, Mechanics & Materials Building Engineering & Civil Engineering
EBP - Explosions, Ballistics & Protection SD - Structural Dynamics
TS - Technical Sciences
To reference this document use:
http://resolver.tudelft.nl/uuid:852f96da-6fef-40ed-8e0f-f782c8361572
TNO identifier
481409
Source
LWAG 2013 - Light-Weight Armour for Defence & Security, Brussel, Belgium, 16-18 October 2013
Document type
conference paper