Effects of Modified Al2O3-Decorated Ionic Liquid on the Mechanical Properties and Impact Resistance of a Polyurethane Elastomer

In this work, a new composite material with excellent dynamic impact resistance and outstanding quasi-static mechanical properties was synthesized. The composite material is composed of a polyurethane elastomer and a novel nano-polymer. The nano-polymer was composed of silane coupling agent-modified alumina microspheres and functionalized ionic liquids by double bond polymerization. The universal testing machine and split Hopkinson pressure bar were used to characterize the compression behavior, strength and energy absorption of the composite materials under static and dynamic conditions. Additionally, the comprehensive mechanical properties of polyurethane elastomer with different nano-polymer loadings (0.5–2.5 wt.%) were studied. The results show that whether it was static compression or dynamic impact, the polyurethane elastomer with 1% nano-polymer had the best performance. For the composite material with the best properties, its compressive yield strength under the static compression was about 61.13% higher than that of the pure polyurethane elastomer, and its energy absorption of dynamic impacts was also increased by about 15.53%. Moreover, the shape memory effect was very good (shape recovery is approximately 95%), and the microscopic damage degree was relatively small. This shows that the composite material with the best properties can withstand high compression loads and high-speed impacts. The developed composite material is a promising one for materials science and engineering, especially for protection against compression and impacts.

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Dynamic Mechanical Properties of CNTs/MoSi2 Composite Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.105-106.75 ◽

2010 ◽

Vol 105-106 ◽

pp. 75-78

Author(s):

Guang Ping Zou ◽

Zhong Liang Chang ◽

Ying Jie Qiao

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Composite Material ◽

Dynamic Performance ◽

Testing Machine ◽

Dynamic Mechanical Properties ◽

Static Compression ◽

Dynamic Mechanical ◽

Waveform Shaping ◽

Mosi2 Composite

Carbon nanotubes (CNTs) are good reinforcement of composite materials, through add appropriate amount of carbon nanotubes to MoSi2 can be improve the strength and toughness of MoSi2. In this paper, the material of CNTs/MoSi2 was made through vacuum hot pressing technology. And the split hopkison press bar (SHPB) technology was used for testing the dynamic mechanical properties of CNTs/MoSi2 composite material which has different proportion of CNTs. In the SHPB experiment, in order to get better waveforms, the waveform shaping technology was used for improving the waveform quality, and also the strain gauge technology was used for testing the real strain of the specimen in the dynamic loading process. Through calculating, the dynamic stress-strain curves which under different high strain rate are given. At the same time, the strength, deformation and other test results are analyzed, and also compared them with the static compression experiment results of the CNTs/MoSi2 specimen which is tested by the electronic universal testing machine, and then obtained the dynamic performance of CNTs/MoSi2 composite material.

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Research on Static Compression Test of Polyurethane Foam/Honeycomb Paperboard Composite Material

The Open Materials Science Journal ◽

10.2174/1874088x01509010064 ◽

2015 ◽

Vol 9 (1) ◽

pp. 64-70

Author(s):

Wang Ju ◽

Liang Jifeng ◽

Lv Lei

Keyword(s):

Composite Material ◽

Composite Materials ◽

Mechanical Behavior ◽

Energy Absorption ◽

Polyurethane Foam ◽

Compression Test ◽

Testing Machine ◽

Compression Tests ◽

Static Compression ◽

Simple Materials

To study the mechanical behavior and energy absorption ability of polyurethane foam/honeycomb paperboard composite material under the static compression test. The static compression tests of polyurethane foam/honeycomb paperboard composite material are conducted by electronic universal testing machine. The mechanical behavior under the condition of static compression and the factors influencing the composite materials’ static cushioning properties were analyzed. Then, a comparison was made based on the energy absorption ability between composite materials and simple materials. The yield stress, strength and other indicators of foam/honeycomb paperboard have doubled the growth after filling polyurethane. The aperture size is the main influencing factor affecting the static cushioning properties of composite material. The energy absorption amount of composite materials is about 1.85 times than the total energy of two simple materials.

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Study on improvement of prefolded energy absorption device to constant resistance and its mechanical properties

Science Progress ◽

10.1177/00368504211036820 ◽

2021 ◽

Vol 104 (3) ◽

pp. 003685042110368

Author(s):

Dong An ◽

Jiaqi Song ◽

Hailiang Xu ◽

Jingzong Zhang ◽

Yimin Song ◽

...

Keyword(s):

Mechanical Properties ◽

Energy Absorption ◽

Compression Test ◽

Side Wall ◽

Concave Side ◽

Displacement Curve ◽

Static Compression ◽

Constant Resistance ◽

The Impact ◽

Force Displacement

When the rock burst occurs, energy absorption support is an important method to solve the impact failure. To achieve constant resistance performance of energy absorption device, as an important component of the support, the mechanical properties of one kind of prefolded tube is analyzed by quasi-static compression test. The deformation process of compression test is simulated by ABAQUS and plastic strain nephogram of the numerical model are studied. It is found that the main factors affecting the fluctuation of force-displacement curve is the stiffness of concave side wall. The original tube is improved to constant resistance by changing the side wall. The friction coefficient affects the folding order and form of the energy absorbing device. Lifting the concave side wall stiffness can improve the overall stiffness of energy absorption device and slow down the falling section of force-displacement curve. It is always squeezed by adjacent convex side wall in the process of folding, with large plastic deformation. Compared with the original one, the improved prefolded tube designed in this paper can keep the maximum bearing capacity ( Pmax), increase the total energy absorption ( E), improve the specific energy absorption (SEA), and decrease the variance ( S2) of force-displacement curve.

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Acoustic Emission and K-S Metric Entropy as Methods for Determining Mechanical Properties of Composite Materials

Sensors ◽

10.3390/s21010145 ◽

2020 ◽

Vol 21 (1) ◽

pp. 145

Author(s):

Lesław Kyzioł ◽

Katarzyna Panasiuk ◽

Grzegorz Hajdukiewicz ◽

Krzysztof Dudzik

Keyword(s):

Mechanical Properties ◽

Acoustic Emission ◽

Composite Material ◽

Composite Materials ◽

Testing Machine ◽

Measurement Data ◽

Entropy Method ◽

Displacement Sensor ◽

Metric Entropy ◽

Plastic Phase

Due to the unique properties of polymer composites, these materials are used in many industries, including shipbuilding (hulls of boats, yachts, motorboats, cutters, ship and cooling doors, pontoons and floats, torpedo tubes and missiles, protective shields, antenna masts, radar shields, and antennas, etc.). Modern measurement methods and tools allow to determine the properties of the composite material, already during its design. The article presents the use of the method of acoustic emission and Kolmogorov-Sinai (K-S) metric entropy to determine the mechanical properties of composites. The tested materials were polyester-glass laminate without additives and with a 10% content of polyester-glass waste. The changes taking place in the composite material during loading were visualized using a piezoelectric sensor used in the acoustic emission method. Thanks to the analysis of the RMS parameter (root mean square of the acoustic emission signal), it is possible to determine the range of stresses at which significant changes occur in the material in terms of its use as a construction material. In the K-S entropy method, an important measuring tool is the extensometer, namely the displacement sensor built into it. The results obtained during the static tensile test with the use of an extensometer allow them to be used to calculate the K-S metric entropy. Many materials, including composite materials, do not have a yield point. In principle, there are no methods for determining the transition of a material from elastic to plastic phase. The authors showed that, with the use of a modern testing machine and very high-quality instrumentation to record measurement data using the Kolmogorov-Sinai (K-S) metric entropy method and the acoustic emission (AE) method, it is possible to determine the material transition from elastic to plastic phase. Determining the yield strength of composite materials is extremely important information when designing a structure.

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The equivalent method of double V-wing honeycombs on the in-plane dynamic impact

Journal of Reinforced Plastics and Composites ◽

10.1177/0731684421990867 ◽

2021 ◽

pp. 073168442199086

Author(s):

Yunfei Qu ◽

Dian Wang ◽

Hongye Zhang

Keyword(s):

Mechanical Properties ◽

Finite Element Analysis ◽

Finite Element ◽

Elastic Modulus ◽

Energy Absorption ◽

Width Ratio ◽

Size Factor ◽

Dynamic Impact ◽

Element Analysis ◽

Equivalent Method

The double V-wing honeycomb can be applied in many fields because of its lower mass and higher performance. In this study, the volume, in-plane elastic modulus and unit cell area of the double V-wing honeycomb were analytically derived, which became parts of the theoretical basis of the novel equivalent method. Based on mass, plateau load, in-plane elastic modulus, compression strain and energy absorption of the double V-wing honeycomb, a novel equivalent method mapping relationship between the thickness–width ratio and the basic parameters was established. The various size factor of the equivalent honeycomb model was denoted as n and constructed by the explicit finite element analysis method. The mechanical properties and energy absorption performance for equivalent honeycombs were investigated and compared with hexagonal honeycombs under dynamic impact. Numerical results showed a well coincidence for each honeycomb under dynamic impact before 0.009 s. Honeycombs with the same thickness–width ratio had similar mechanical properties and energy absorption characteristics. The equivalent method was verified by theoretical analysis, finite element analysis and experimental testing. Equivalent honeycombs exceeded the initial honeycomb in performance efficiency. Improvement of performance and weight loss reached 173.9% and 13.3% to the initial honeycomb. The double V-wing honeycomb possessed stronger impact resistance and better load-bearing capacity than the hexagonal honeycomb under impact in this study. The equivalent method could be applied to select the optimum honeycomb based on requirements and improve the efficiency of the double V-wing honeycomb.

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Microstructural and Dynamic Mechanical Characterization of Biodegradable Magnesium-Calcium Alloy for Orthopedic Implants

Volume 2: Processing ◽

10.1115/msec2014-4064 ◽

2014 ◽

Author(s):

V. S. Brooks ◽

Y. B. Guo

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

High Strain ◽

Split Hopkinson Pressure Bar ◽

Dynamic Compression ◽

Orthopedic Implants ◽

Strain Rates ◽

High Strain Rates ◽

Static Compression ◽

Metallic Biomaterial

Magnesium-Calcium (Mg-Ca) alloy is an emerging metallic biomaterial for manufacturing biodegradable orthopedic implants. However, very few studies have been conducted on mechanical properties of the bi-phase Mg-Ca alloy, especially at the high strain rates often encountered in manufacturing processes. The mechanical properties are critical to design and manufacturing of Mg-Ca implants. The objective of this study is to study the microstructural and mechanical properties of Mg-Ca0.8 (wt %) alloy. Both elastic and plastic behaviors of the Mg-Ca0.8 alloy were characterized at different strains and strain rates in quasi-static tension and compression testing as well as dynamic split-Hopkinson pressure bar (SHPB) testing. It has been shown that Young’s modulus of Mg-Ca0.8 alloy in quasi-static compression is much higher than those at high strain rates. Yield strength and ultimate strength of the material are very sensitive to strain rates and increase with strain rate in compression. Strain softening also occurs at large strains in dynamic compression. Furthermore, quasi-static mechanical behavior of the material in tension is very different from that in compression. The stress-strain data was repeatable with reasonable accuracy in both deformation modes. In addition, a set of material constants for the internal state variable plasticity model has been obtained to model the dynamical mechanical behavior of the novel metallic biomaterial.

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Mechanical Properties of PVC/ABS Composite Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.217-218.1170 ◽

2011 ◽

Vol 217-218 ◽

pp. 1170-1173

Author(s):

Wei Wei Qiao ◽

Hui Wang ◽

Yan Hua Zhao ◽

Yi Xia Han

Keyword(s):

Mechanical Properties ◽

Composite Material ◽

Testing Machine ◽

Impact Testing ◽

Elongation At Break ◽

Poly Vinyl Chloride ◽

Maximum Value ◽

Material Testing Machine ◽

The Impact ◽

Butadiene Styrene

We investigate the mechanical properties of Poly Vinyl Chloride (PVC)/ acrylnitrile-butadiene-styrene copolymer (ABS) composite material with an impact testing machine，a material testing machine and other accessory devices. The result shows that the mechanical properties of PVC/ABS composite are a function of composition, the addition of ABS improved the mechanical properties of PVC/ ABS composite，the impact strength and elongation at break rise significantly with increasing ABS content in PVC/ABS composite and appears maximum value，While the tensile strength and modulus almost decrease monotonously with increasing ABS content in PVC/ABS composite.

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Experimental Study of Mechanical Properties and Impact-Induced Reaction Characteristics of PTFE/Al/CuO Reactive Materials

Materials ◽

10.3390/ma13010066 ◽

2019 ◽

Vol 13 (1) ◽

pp. 66 ◽

Cited By ~ 2

Author(s):

Jingyuan Zhou ◽

Liangliang Ding ◽

Wenhui Tang ◽

Xianwen Ran

Keyword(s):

Mechanical Properties ◽

Constitutive Model ◽

Split Hopkinson Pressure Bar ◽

Hopkinson Pressure Bar ◽

Sem Images ◽

Static Compression ◽

Drop Hammer ◽

Reactive Materials ◽

Reaction Characteristics ◽

Induced Reaction

Metal/fluoropolymer materials are typical reactive materials. Polytetrafluoroethylene (PTFE)/Al/CuO reactive materials were studied in this research. Scanning electron microscopy (SEM), quasi-static compression, the Split Hopkinson pressure bar test, and the drop hammer test were used to study the mechanical properties and induced reaction characteristics of the reactive materials with different Al/CuO thermite contents and different particle sizes. SEM images of the samples demonstrate that the reactive materials were mixed evenly. The compression test results show that, if the particle size of PTFE was too small, the strength of reactive materials after sintering was reduced. After sintering, with the increase in the content of Al/CuO thermite, the strength of the micro-sized PTFE/Al/CuO firstly increased and then decreased. The Johnson–Cook constitutive model can be used to characterize the reactive materials, and the parameters of the Johnson–Cook constitutive model of No. 3 reactive materials (PTFE/Al:Al/CuO = 3:1) were obtained. The reliability of the parameters was verified by numerical simulation. Drop hammer tests show that the addition of Al/CuO aluminothermic materials or the use of nano-sized PTFE/Al reactive materials can significantly improve the sensitivity of the material. The research in this paper can provide a reference for the preparation, transportation, storage, and application of reactive materials.

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Dynamic Compression Behavior of Lotus-Type Porous Iron

Materials Science Forum ◽

10.4028/www.scientific.net/msf.658.193 ◽

2010 ◽

Vol 658 ◽

pp. 193-196

Author(s):

Masakazu Tane ◽

Tae Kawashima ◽

Keitaro Horikawa ◽

Hidetoshi Kobayashi ◽

Hideo Nakajima

Keyword(s):

Split Hopkinson Pressure Bar ◽

Dynamic Compression ◽

Testing Machine ◽

Porous Iron ◽

Compression Tests ◽

Hopkinson Pressure Bar ◽

Static Compression ◽

Plateau Stress ◽

Stress Region ◽

Quasi Static Compression

Dynamic and quasi-static compression tests were conducted on lotus-type porous iron with porosity of about 50% using the split Hopkinson pressure bar method and universal testing machine, respectively.　In the dynamic compression parallel to the pore direction, a plateau stress region appears where deformation proceeds at nearly constant stress, while the plateau stress region does not appear in the quasi-static compression. The plateau stress region is probably caused by the buckling deformation of matrix iron which occurs only in the dynamic compression. In contrast, the compression perpendicular to the orientation direction of pores exhibits no plateau-stress regions in the both dynamic and quasi-static compression.

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Size Effect Analysis during Material Deformation with High Strain Rate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.589-590.198 ◽

2013 ◽

Vol 589-590 ◽

pp. 198-203

Author(s):

Feng Jiang ◽

Lan Yan ◽

Zhong Wei Hu ◽

Yi Ming(Kevin) Rong

Keyword(s):

Shear Stress ◽

Size Effect ◽

Strain Rate ◽

Split Hopkinson Pressure Bar ◽

Failure Strain ◽

Testing Machine ◽

Hopkinson Pressure Bar ◽

Dynamic Impact ◽

Impact Tests ◽

Material Deformation

The goal of this study is to analyze the material deformation behavior in the micron level by quasi-static and dynamic impact tests of hat shaped specimen. Three type of specimen with different shear ring thicknesses (800μm, 400μm, 50μm) were designed. The quasi-static and dynamic impact tests were performed by electronic universal testing machine and split Hopkinson pressure bar (SHPB) respectively. During the material deformation in the SHPB test, the value scope of strain is 0 to 9 while the value scope of strain rate is 0.001s-1 to 400000s-1. The size effect phenomenon on shear stress and failure strain with different shear ring thickness was investigated. The shear stress and failure strain of material increases with the decrease of shear ring thickness. And the size effect phenomenon was weakened with the increase of strain rate.

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