Results 191 to 200 of about 12,040 (234)
Some of the next articles are maybe not open access.
Measurement Science and Technology, 1995
The conventional split Hopkinson pressure bar system for materials testing at high strain rates produces loading pulses that have a high level of oscillation superimposed on their approximately trapezoidal shape. These oscillations, which are a consequence of the short risetime of the loading pulse produced by the impact of a projectile, cause ...
D J Parry, A G Walker, P R Dixon
openaire +1 more source
The conventional split Hopkinson pressure bar system for materials testing at high strain rates produces loading pulses that have a high level of oscillation superimposed on their approximately trapezoidal shape. These oscillations, which are a consequence of the short risetime of the loading pulse produced by the impact of a projectile, cause ...
D J Parry, A G Walker, P R Dixon
openaire +1 more source
Split Bar Hopkinson with Springs Striker Bar Launcher
Applied Mechanics and Materials, 2014Research on the dynamic strength of various materials such as metallic materials, polymers, concrete has been done by many researchers. The Split Hopkinson Bar method is still used to produce a high strain rate. In this method, a striker bar is usually launched using pressurized gas.
Agus Sigit Pramono +2 more
openaire +1 more source
Experimental Mechanics, 1980
Experiments in which pressure pulses are propagated in a column of fluid held in a stiff tube are described. A parameter, η, which characterizes the tube stiffness has been defined and a one-dimensional model of the wave propagation which includes dissipation both in the volume of the fluid and at the wall of the containing tube has been developed.
openaire +1 more source
Experiments in which pressure pulses are propagated in a column of fluid held in a stiff tube are described. A parameter, η, which characterizes the tube stiffness has been defined and a one-dimensional model of the wave propagation which includes dissipation both in the volume of the fluid and at the wall of the containing tube has been developed.
openaire +1 more source
Construction and Building Materials, 2022
Abstract In the comparison of Hopkinson bundle bar (HBB) system and the large diameter split Hopkinson pressure bar (SHPB) system, the influence of bar diameter on the dispersion effect of the one-dimensional longitudinal wave is analyzed theoretically firstly.
Nao Lv +4 more
openaire +1 more source
Abstract In the comparison of Hopkinson bundle bar (HBB) system and the large diameter split Hopkinson pressure bar (SHPB) system, the influence of bar diameter on the dispersion effect of the one-dimensional longitudinal wave is analyzed theoretically firstly.
Nao Lv +4 more
openaire +1 more source
Experimental techniques for the Hopkinson bar
AIP Conference Proceedings, 2000Several factors influence the accuracy of results when using the Split Hopkinson bar. These include longitudinal wave dispersion, and impedance mismatch of the bars with the specimens. In this paper, we discuss our approach to choosing specimen dimensions based on their impedance, thereby improving the transmitted stress signal-to-noise ratio.
openaire +1 more source
HOPKINSON BAR STUDIES OF A PBX SIMULANT
AIP Conference Proceedings, 2008Experiments were carried out, at a strain rate of 1600 s−1, to characterise an HTPB/sugar propellant simulant within the temperature range of 50 °C to −100 °C. Optical techniques, namely high‐speed photography with digital speckle analysis for flow visualisation, and line‐laser occlusion to measure diametric expansion, were deployed.
Daniel R. Drodge +8 more
openaire +1 more source
1999
Most materials show a significant change in mechanical behaviour as the rate of strain (the deformation rate) is increased1 (see High Strain Rate Effects). This is particularly evident at the high strain rates (>102 s −1) which occur under impact or explosive loading conditions.
openaire +1 more source
Most materials show a significant change in mechanical behaviour as the rate of strain (the deformation rate) is increased1 (see High Strain Rate Effects). This is particularly evident at the high strain rates (>102 s −1) which occur under impact or explosive loading conditions.
openaire +1 more source
Discussions on Standardization of Hopkinson Bars Technique
2007It is well known that the constitutive behaviour of most materials exhibits rate sensitivity and that the rate dependent (tensile/compressive) properties of such materials should be experimentally studied. The Split Hopkinson Bar (SHB) technique has been successfully applied to investigate the visco-elastic and visco-plastic behaviour of plastics and ...
L. M. Yang, Li Song, Li-Li Wang
openaire +1 more source
The Origins of the Hopkinson Bar Technique
2018Although Bertram Hopkinson had a research interest in the dynamic strengths of materials, the bar technique he published in 1914 was developed to roughly determine the shapes of stress pulses produced by bullet impact and explosions. His pressure bar proved useful to the British explosives and armour industry during the Great War allowing them to ...
openaire +1 more source
Dispersion Investigation in the Split Hopkinson Pressure Bar
Journal of Engineering Materials and Technology, 1990Dispersion of an elastic wave propagating in a 76.2-mm-diameter (3 in.) Split Hopkinson Pressure Bar system was investigated with two consecutive pulses recorded in the transmitter bar. Assuming that the dispersive high frequency oscillatory components riding on the top of the main pulse originate from the first mode vibration, the dispersion was ...
J. C. Gong, L. E. Malvern, D. A. Jenkins
openaire +1 more source