Viscoelastic characterization of polymers using instrumented indentation. II. Dynamic testing

2005 ◽  
Vol 43 (14) ◽  
pp. 1812-1824 ◽  
Author(s):  
C. C. White ◽  
M. R. VanLandingham ◽  
P. L. Drzal ◽  
N.-K. Chang ◽  
S.-H. Chang
2008 ◽  
Vol 136 ◽  
pp. 83-92 ◽  
Author(s):  
M.V. Hosur ◽  
Jessie B. Mayo Jr. ◽  
E. Wetzel ◽  
S. Jeelani

Kevlar has demonstrated the ability to protect well against ballistic threats but has low resistance to puncture. Correctional Kevlar has shown good resistance to puncture. However, the fabric is expensive, difficult to manufacture because of its tight weave construction, and has limited protection against ballistic threats. In an effort to produce materials that are less bulky, more flexible, and resistant to puncture, thermoplastic-Kevlar (TP-Kevlar) composites have been examined. Kevlar fabric was impregnated with thermoplastic film using a hot press to produce the composites. Static and dynamic puncture resistant properties of the TP-Kevlar composites were investigated using a National Institute of Justice (NIJ Standard 0115.00) Stab Tower. The TP-films used in this study were polyethylene, Surlyn, and co extruded-Surlyn, which is a co extrusion of Surlyn and polyethylene. Response of the polyethylene (PE)-Kevlar composites, Surlyn-Kevlar composites, and co extruded (COEX)-Kevlar composites to spike and knife threats under static and dynamic conditions were compared with that of neat Kevlar. The infusion of thermoplastic films into the Kevlar fabric was shown to dramatically increase puncture resistance during quasi-static and dynamic testing with spikes. The TP-film type also made a difference when examining the resistance on a comparative basis of the TP-Kevlar targets. The TP-Kevlar composite targets showed more resistance to quasi-static spike testing than quasi-static knife testing. Weapon comparisons revealed that the TP-Kevlar composite targets had more resistance to dynamic knife testing than dynamic spike testing.


2020 ◽  
Vol 9 (6) ◽  
pp. 884-894
Author(s):  
A. R. H. Midawi ◽  
N. Huda ◽  
C. H. M. Simha ◽  
A. P. Gerlich

2020 ◽  
Vol 138 ◽  
pp. 105608 ◽  
Author(s):  
John Pachón-Morales ◽  
Julien Colin ◽  
Joel Casalinho ◽  
Patrick Perré ◽  
François Puel

2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Scott A. Smith ◽  
Matthew R. W. Brake ◽  
Christoph W. Schwingshackl

Abstract This work refines a recently formalized methodology proposed by D.J. Ewins consisting of ten steps for model validation of nonlinear structures. This work details, through a series of experimental studies, that many standard test setup assumptions that are made when performing dynamic testing are invalid and need to be evaluated for each structure. The invalidation of the standard assumptions is due to the presence of nonlinearities, both known and unrecognized in the system. Complicating measurements, many nonlinearities are currently characterized as constant properties instead of variables that exhibit dependency on system hysteresis and actuation amplitude. This study reviews current methods for characterizing nonlinearities and outlines gaps in the approaches. A brief update to the CONCERTO method, based on the accelerance of a system, is derived for characterizing a system’s nonlinearities. Finally, this study ends with an updated methodology for model validation and the ramifications for modeling assemblies with nonlinearities are discussed.


2011 ◽  
Vol 10 ◽  
pp. 3162-3172 ◽  
Author(s):  
Young-Cheon Kim ◽  
Won-Seok Song ◽  
Jong-Heon Kim ◽  
Kug-Hwan Kim ◽  
Dongil Kwon

2017 ◽  
Vol 108 ◽  
pp. 58-67 ◽  
Author(s):  
Ghailen BEN Ghorbal ◽  
Arnaud Tricoteaux ◽  
Anthony Thuault ◽  
Ghislain Louis ◽  
Didier Chicot

Sign in / Sign up

Export Citation Format

Share Document