@article{Jones:2015:10.3791/52463,
author = {Jones, DR and Chapman, DJ and Eakins, DE},
doi = {10.3791/52463},
journal = {Journal of Visualized Experiments},
title = {A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation},
url = {http://dx.doi.org/10.3791/52463},
volume = {100},
year = {2015}
}

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TY  - JOUR
AB  - The dynamic fracture of a body is a late-stage phenomenon typically studied under simplified conditions, in which a sample is deformed underuniform stress and strain rate. This can be produced by evenly loading the inner surface of a cylinder. Due to the axial symmetry, as the cylinderexpands the wall is placed into a tensile hoop stress that is uniform around the circumference. While there are various techniques to generatethis expansion such as explosives, electromagnetic drive, and existing gas gun techniques they are all limited in the fact that the sample cylindermust be at room temperature. We present a new method using a gas gun that facilitates experiments on cylinders from 150 K to 800 K with aconsistent, repeatable loading. These highly diagnosed experiments are used to examine the effect of temperature on the fracture mechanismsresponsible for failure, and their resulting influence on fragmentation statistics. The experimental geometry employs a steel ogive located insidethe target cylinder, with the tip located about halfway in. A single stage light gas gun is then used to launch a polycarbonate projectile into thecylinder at 1,000 m/sec-1. The projectile impacts and flows around the rigid ogive, driving the sample cylinder from the inside. The use of a nondeformingogive insert allows us to install temperature control hardware inside the rear of the cylinder. Liquid nitrogen (LN2) is used for coolingand a resistive high current load for heating. Multiple channels of upshifted photon Doppler velocimetry (PDV) track the expansion velocityalong the cylinder enabling direct comparison to computer simulations, while High speed imaging is used to measure the strain to failure. Therecovered cylinder fragments are also subject to optical and electron microscopy to ascertain the failure mechanism.
AU  - Jones,DR
AU  - Chapman,DJ
AU  - Eakins,DE
DO  - 10.3791/52463
PY  - 2015///
SN  - 1940-087X
TI  - A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
T2  - Journal of Visualized Experiments
UR  - http://dx.doi.org/10.3791/52463
UR  - http://hdl.handle.net/10044/1/27054
VL  - 100
ER  - 

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