scholarly journals A Study on Measuring Distribution of Temperature for Instrumented Taylor Impact Test

2021 ◽  
Vol 250 ◽  
pp. 01028
Author(s):  
Chong Gao ◽  
Takeshi Iwamoto
Keyword(s):  
Strain Rate ◽  
Impact Test ◽  
Split Hopkinson Pressure Bar ◽  
Infrared Detector ◽  
Measuring System ◽  
Pure Aluminium ◽  
Local Point ◽  
Taylor Impact ◽  
Taylor Impact Test ◽  
The Impact

It is a challenge to apply the infrared detector to a test at higher strain rate because lots of articles report that the detector has an extremelyhigh responsiveness. However, all the research works about the measurement of temperature is focused on 103 s-1 of the strain rate achieved by the split Hopkinson pressure bar test. To evaluate the thermo-mechanical behaviour of materials in higher strain rate range, a method for measuring the temperature in Taylor impact test is required to establish. Additionally, a use of the fiber should be considered to protect the detector from any damages by the impact of the specimen and realize the measurement in the point-like area. In this study, an optically-measuring system of temperature with the infrared detector and PIR fiber is designed. Then, the designed system is introduced into the apparatus based on the instrumented Taylor impact test proposed recently. The temperature rise at a local point on the surface of pure aluminium is measured during the test. Then, a calculation for distribution of temperature from a heat conduction equation is proposed.

Verification of Taylor Impact Test by Using Force Sensing Block

2014 ◽  
Vol 626 ◽  
pp. 444-449
Author(s):  
Fumiaki Iwasaki ◽  
Nobuhiko Kii ◽  
Takeshi Iwamoto
Keyword(s):  
Strain Rate ◽  
External Force ◽  
Impact Test ◽  
Split Hopkinson Pressure Bar ◽  
Time History ◽  
Rigid Wall ◽  
Force Sensing ◽  
Past Study ◽  
Taylor Impact ◽  
Taylor Impact Test

In the Taylor impact test, obtained strain rate becomes in a range of 103~105/s corresponding to penetration of space debris to a space structure. According to this test, a stress value can be calculated by theoretical formulae. However, the formulae include some assumptions and the external force acting on a specimen is not directly measured by using the formulae. In the past study, the split Hopkinson pressure bar (SHPB) is employed instead of a use of a rigid wall which the specimen collides. However, there are two difficulties on this method. The first one is to be a similar range of measurable strain rate to the SHPB technique and the second is to require a sufficiently-large space for a testing apparatus. In contrast, by introducing a force sensing block, the apparatus becomes compact and longer measurable time is realized compared with the SHPB technique. Therefore, the stress value can be measured with higher precision since an extensive range of strain rate can be measurable. In this study, to enhance the precision of the test, it is suggested that the force sensing block is placed just behind the rigid wall for a direct measurement of a time history of external force.

Influence of Temperature on Dynamic Behavior of Rubber Materials by Taylor Impact Test

2011 ◽  
Vol 673 ◽  
pp. 83-88 ◽  
Author(s):  
Hyung Seop Shin ◽  
Sung Su Park ◽  
Joon Hong Choi
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
Deformation Behavior ◽  
High Speed ◽  
Impact Test ◽  
High Strain ◽  
High Speed Photography ◽  
Impact Tests ◽  
Taylor Impact ◽  
Taylor Impact Test

The understanding of the deformation behavior of rubber materials under high strain-rate or high loading-rate conditions will be important in their impact applications adopting significant viscoelastic behavior. Taylor impact test has originally used to determine the average dynamic yield strength of metallic materials at high strain rates, but it also can be used to examine the overall deformation behavior of rubbers representing large elastic deformation by using a high-speed photography technique. Taylor impact tests of rubber materials were carried out in the velocity range between 100~250 m/s using a 20 mm air gun. In order to investigate the overall dynamic deformation behavior of rubber projectiles during Taylor impact test, a 8-Ch high-speed photography system which provides a series of images at each elapsed time was incorporated. Three kinds of rubber materials with different Tg (glass transition temperature) were supplied. The bulging behavior of rubber projectile could be evaluated quantitatively by digitizing images taken. Taylor impact tests at various temperature levels were conducted to predict the bulging behavior of rubbers at high strain rate.

scholarly journals Investigation on the Application of Taylor Impact Test to High-G Loading

2021 ◽  
Vol 8 ◽  
Author(s):  
Li Juncheng ◽  
Chen Gang ◽  
Lu Yonggang ◽  
Huang Fenglei
Keyword(s):  
Pulse Duration ◽  
Impact Loading ◽  
Impact Test ◽  
Impact Load ◽  
Low Cost ◽  
Large Mass ◽  
Impact Testing ◽  
Taylor Impact ◽  
Taylor Impact Test ◽  
The Impact

Taylor impact test is characterized by high impact energy, low cost, and good repeatability, giving it the technical foundation and development potential for application in high-g loading. In this paper, the feasibility of performing high-g load impact testing to a missile-borne recorder by conducting Taylor impact test was studied by combining simulation analyses with experimental verification. Acccording to the actual dimensions of the missile-borne recorder, an experimental piece was designed based on the Taylor impact principle. The impact loading characteristics of the missile-borne recorder were then simulated and analyzed at different impact velocities. In addition, the peak acceleration function and the pulse duration function of the load were fitted to guide the experimental design. A Taylor-Hopkinson impact experiment was also conducted to measure the impact load that was actually experienced by the missile-borne recorder and the results were compared with the results of strain measurements on the Hopkinson incident bar. The results showed that the peak value of impact load, the pulse duration and the waveform of the actual experimental results were in good agreement with the results predicted by the simulations. Additionally, the strain data measured on the incident bar could be used to verify or replace the acceleration testing of the specimen to simplify the experimental process required. Based on the impact velocity, high-g loading impact was achieved with peak values in the 7,000–30,000 g range and durations of 1.3–1 ms, and the waveform generated was a sawtooth wave. The research results provide a new approach for high amplitude and long pulse duration impact loading to large-mass components, and broaden the application field of Taylor impact test.

Impact Compressive Properties of Foamed Film with Closed Cell

2014 ◽  
Vol 566 ◽  
pp. 134-139 ◽  
Author(s):  
Hiroyuki Yamada ◽  
Ryo Okui ◽  
Nagahisa Ogasawara ◽  
Hidetoshi Kobayashi ◽  
Kinya Ogawa
Keyword(s):  
Strain Rate ◽  
Impact Test ◽  
Split Hopkinson Pressure Bar ◽  
Rate Dependency ◽  
Hopkinson Pressure Bar ◽  
Compressive Properties ◽  
Static Test ◽  
Closed Cell ◽  
Pressure Bar ◽  
The Impact

The compressive properties of foamed polyethylene (PE) film with a closed cell for electronic devices have been investigated. A commercial closed cell foamed PE film with a density of 330 kg/m3 was used. Quasi-static testing was carried out at strain rates of 10−3 to 10−1 s−1. The strain rate of the impact test was approximately 105 s−1 by means of split Hopkinson pressure bar method. Within the set of experiments, the compressive stress increased with the strain rate in both the quasi-static and impact test. In particular, the flow stress increased substantially with the increasing strain rate in the impact deformation. At strains of less than 0.4, the trapped air was locally compressed within the cells, which led to the strain rate dependency of strength in the quasi-static test and the impact test.

An Analytical Interpretation of High Strain Rate Material Behavior During Early Time Plastic Deformation in the Taylor Impact Test

1992 ◽  
Author(s):  
S. E. Jones ◽  
Paul J. Maudlin ◽  
Peter P. Gillis ◽  
Joseph C. Foster
Keyword(s):  
Plastic Deformation ◽  
Strain Rate ◽  
Impact Test ◽  
Early Time ◽  
Material Behavior ◽  
Deformation Phase ◽  
Taylor Impact ◽  
Taylor Impact Test ◽  
Rate Relation ◽  
The Continuum

Abstract Using information from experiments and continuum mechanics code calculations, an analytical stress/strain-rate relation is developed. This relation is valid during the early time plastic deformation phase of the Taylor impact test. The results show good correlation between experiment and the continuum code predictions.

scholarly journals Load Characteristics in Taylor Impact Test on Projectiles with Various Nose Shapes

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 713
Author(s):  
Jun-Cheng Li ◽  
Gang Chen ◽  
Feng-Lei Huang ◽  
Yong-Gang Lu
Keyword(s):  
Impact Velocity ◽  
Impact Analysis ◽  
Impact Test ◽  
Impact Load ◽  
Loading Test ◽  
Impact Theory ◽  
Nose Shape ◽  
Taylor Impact ◽  
Taylor Impact Test ◽  
The Impact

This study focused on the impact load produced by a projectile and its potential application in the Taylor impact test. Taylor impact tests were designed and carried out for projectiles with four types of nose shapes, and the impact deformation characteristics and variation of the impact load as a function of the nose shape and impact velocity were studied. The overall high g loading experienced by the projectile body during the impact was discussed, and based on classical Taylor impact theory, impact analysis models for the various nose-shape projectiles were established and the causes of the different impact load pulse shapes were analyzed. This study reveals that the nose shape has a significant effect on the impact load waveform and pulse duration characteristics, while the impact velocity primarily affects the peak value of the impact load. Thus, the loading of specific impact environments could be regulated by the projectile nose shape design and impact velocity control, and the impact load could be simulated. Research results support the assumption that the Taylor impact test can be applied to high g loading test.

Evaluation of Dynamic Deformation Properties of Metallic Materials with Different Crystal Structures Using Taylor Impact Test

2014 ◽  
Vol 566 ◽  
pp. 146-151 ◽  
Author(s):  
Kyung Oh Bae ◽  
Hyung Seop Shin ◽  
Hoon Huh ◽  
Lee Ju Park ◽  
Hyung Won Kim
Keyword(s):  
Strain Rate ◽  
Deformation Behavior ◽  
High Speed ◽  
Impact Test ◽  
Dynamic Deformation ◽  
Metallic Materials ◽  
Dynamic Yield Strength ◽  
Taylor Impact ◽  
Dynamic Yield ◽  
The Impact

Investigations on dynamic deformation behavior of metallic materials under high strain rate have been conducted. In this study, the deformation behaviors of metallic materials with different crystal structures were examined through Taylor impact test. As representative materials, HSA800 (body-centered cubic: BCC), OFHC (face-centered cubic: FCC) and Ti-6Al-4V (hexagonal close-packed : HCP) were adopted. Taylor impact tests were carried out in the impact velocity range of 100~270 m/s for BCC and FCC materials and 150~330 m/s for Ti-alloy one. In addition, an 8-Ch high-speed photography system was used to provide a series of images representing the plastic deformation behavior of a projectile during Taylor test. The dynamic yield strength and the strain rate were calculated based on the contact time duration of projectile determined from high-speed images. From the result, the strain rate dependency of the dynamic yield strength varied depending on the material adopted. Bulging occurred at the impact part was more significant in FCC material than in BCC one, while a shear band occurred in the Ti-alloy specimen when the impact velocity of projectile exceeded 270 m/s.

scholarly journals An axisymmetric model for Taylor impact test and estimation of metal plasticity

2015 ◽  
Vol 471 (2174) ◽  
pp. 20140556 ◽  
Author(s):  
Sukanta Chakraborty ◽  
Amit Shaw ◽  
Biswanath Banerjee
Keyword(s):  
Impact Test ◽  
Deformation Behaviour ◽  
Spatial And Temporal Variation ◽  
Radial Deformation ◽  
Axisymmetric Model ◽  
Proposed Model ◽  
Taylor Impact ◽  
Taylor Impact Test ◽  
The Impact ◽  
Constitutive Parameters

The impact of a flat-ended cylindrical rod onto a rigid stationary anvil, often known as the Taylor impact test, is studied. An axisymmetric model is developed to capture the deformation behaviour of the rod after impact. The most distinctive feature of the proposed model is that it takes into account the spatial and temporal variation of both longitudinal and radial deformation and consequently the strains and strain rates. The final deformed shapes and time histories of different field variables, as obtained from the model, are found to be in good agreement with corresponding experimental and numerical results reported in the literature. The proposed model is then used to formulate an inverse framework to estimate the Johnson–Cook constitutive parameters. In the inverse formulation, the objective function is constructed using the final deformed length and diameter at the impact end of the retrieved rod. Finally, the potential of the proposed model in estimating material parameters is illustrated through some examples.

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