Compression Properties and Its Prediction of Wood-Based Sandwich Panels with a Novel Taiji Honeycomb Core

The transverse compression property is one of most important aspects of the mechanical performance of a sandwich structure with a soft core. An experiment, analytical method and three digital strain measurement systems were applied to investigate the compression behavior and the failure mechanism for a wood-based sandwich structure with a novel Taiji honeycomb core. The results show that the structure of the Taiji honeycomb can improve dramatically on compression strength and modulus of composite compared to that of a traditional hexagonal one. There was no obvious deflection in the transverse direction detected by the three digital images before the buckling of the honeycomb occurred. An analytical equation between the key structure parameters and properties of the composite were applied to predict its threshold stresses and modulus. The properties of the core determine the strength of the entire structure, but the compression strength decreases slightly with an elevated core thickness, and its effect on the compression modulus can be neglected. Both the surface sheets and loading speed have little impact on the compression strength and modulus, respectively.

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Effect of Basalt Intraply Fiber Hybridization on the Compression Behavior of Filament Wound Composite Pipes

International Polymer Processing ◽

10.1515/ipp-2020-4005 ◽

2021 ◽

Vol 36 (2) ◽

pp. 193-204

Author(s):

Ö. Özbek ◽

Ö. Y. Bozkurt ◽

A. Erkliğ

Keyword(s):

Axial Compression ◽

Compression Strength ◽

Basalt Fiber ◽

Radial Compression ◽

Compression Tests ◽

Compression Behavior ◽

Compression Properties ◽

Fiber Winding ◽

Composite Pipes ◽

Hybrid Carbon

Abstract The current study deals with the effect of basalt fiber hybridization on the compressive properties of composite pipes reinforced with glass fiber and carbon fiber. Hybrid and non-hybrid fiber reinforced pipes (FRPs) were fabricated through wet filament winding technique. Intraply fiber winding structure in which different fiber types were simultaneously wound at the layer was employed for the hybridization. The FRP samples wound by different fiber winding angles (± (40°), ± (55°), ± (70°)) were prepared in order to gain a better insight on the influence of basalt intraply fiber hybridization. The compression properties of FRP samples were experimentally determined by quasi-static compression tests using external parallel-plates for both the axial and radial directions. The non-hybrid carbon FRP pipes showed the maximum axial compression strength in parallel to the highest strength and lowest ductility of carbon fibers, while the minimum axial compression strength was obtained for the non-hybrid pipes reinforced with basalt fibers that, in comparison, exhibit much less strength and higher ductility. The pipes submitted to the axial compression tests predominantly failed due to the development of cracks and buckling along the fiber direction. While the inclusion of basalt fiber reduced the axial compression behavior of the non-hybrid carbon and glass FRP samples, it improved that behavior in the radial compression tests. Delamination was determined as the major failure mode for the damaged FRPs under radial compression. It is found that the incorporation of basalt fiber provides improvements in radial compression properties as opposed to axial compression properties and in the same manner the increment in fiber winding angle makes a positive contribution to radial compression properties.

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Numerical Analysis on Vibro-Acoustic Behavior of Honeycomb Core Sandwich Structure with FG-CNT-Reinforced Polymer Composite Facings

Iranian Journal of Science and Technology Transactions of Mechanical Engineering ◽

10.1007/s40997-021-00462-0 ◽

2021 ◽

Author(s):

Vinod S. Bhagat ◽

Nivish George ◽

M. P. Arunkumar ◽

Jeyaraj Pitchaimani ◽

M. C. Lenin Babu

Keyword(s):

Numerical Analysis ◽

Polymer Composite ◽

Sandwich Structure ◽

Acoustic Behavior ◽

Honeycomb Core ◽

Reinforced Polymer

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On the mechanical performance of honeycomb-core sandwich L-joint under bending load: an experimental-numerical study

Journal of Adhesion Science and Technology ◽

10.1080/01694243.2021.1959773 ◽

2021 ◽

pp. 1-23

Author(s):

Wenbin Hou ◽

Jianhua Li ◽

Lin Sang ◽

Liang Ying ◽

Xiao Han

Keyword(s):

Mechanical Performance ◽

Numerical Study ◽

Honeycomb Core ◽

Bending Load

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Enhancement of the Tensile and the Compression Properties for Heat- Cured Acrylic Resin Denture Base Materials

Baghdad Science Journal ◽

10.21123/bsj.15.4.449-454 ◽

2018 ◽

Vol 15 (4) ◽

pp. 449-454

Author(s):

Baghdad Science Journal

Keyword(s):

Polymethyl Methacrylate ◽

Compression Strength ◽

Base Material ◽

Acrylic Resin ◽

Tensile Tests ◽

Strength Test ◽

Denture Base ◽

Compression Properties ◽

Base Materials ◽

Styrene Butadiene

This work aims to investigate the tensile and compression strengths of heat- cured acrylic resin denture base material by adding styrene-butadiene (S- B) to polymethyl methacrylate (PMMA). The most well- known issue in prosthodontic practice is fracture of a denture base. All samples were a blend of (90%, 80%) PMMA and (10%, 20%) S- B powder melted in Oxolane (Tetra hydro furan). These samples were chopped down into specimens of dimensions 100x10x2.5mm to carry out the requirements of tensile tests. The compression strength test specimens were shaped into a cylinder with dimensions of 12.7mm in diameter and 20mm in length. The experimental results show a significant increase in both tensile and compression strengths when compared to control (standard) results for the preparation material.

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Effect of Core Thickness and Intermediate Layers on Mechanical Properties of Polypropylene Honeycomb Multi-Layer Sandwich Structures

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0002 ◽

2014 ◽

Vol 59 (1) ◽

pp. 11-16 ◽

Cited By ~ 12

Author(s):

J. Arbaoui ◽

Y. Schmitt ◽

J.-L. Pierrot ◽

F.-X. Royer

Keyword(s):

Mechanical Properties ◽

Sandwich Structures ◽

Bending Test ◽

Honeycomb Core ◽

Lightweight Construction ◽

Specific Strength ◽

High Specific Strength ◽

Intermediate Layers ◽

Core Thickness ◽

Strength And Stiffness

Abstract Sandwich structures are widely used in lightweight construction especially in aerospace industries because of their high specific strength and stiffness. This paper investigates the effect of core thickness and intermediate layers on the mechanical properties of a polypropylene honeycomb core/composite facing multilayer sandwich structure under three points bending. We developed a theoretical model which makes it possible to calculate the shear properties in multi-cores. The results obtained by this model are agreed with our experimental results, and the results obtained with bending test showed that the mechanical properties of the composite multilayer structures increase with core thickness and intermediate layers.

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Evaluation of sandwich panels with composite tube-reinforced foam core under bending and flatwise compression

Journal of Sandwich Structures & Materials ◽

10.1177/1099636218798161 ◽

2018 ◽

Vol 22 (2) ◽

pp. 480-493 ◽

Cited By ~ 1

Author(s):

Kenan Cinar

Keyword(s):

Thermal Conductivity ◽

Sandwich Structure ◽

Bending Stiffness ◽

Core Material ◽

Foam Core ◽

Compression Tests ◽

Composite Tubes ◽

Low Thermal Conductivity ◽

Compression Performance ◽

Compression Properties

In some applications such as roofs and walls, it is important to supply low thermal conductivity and high bending stiffness to structures. Generally, foam materials are preferred, which have low thermal conductivity. However, bending stiffness and compression properties of foam materials are low. In this study, composite tubes were inserted to the foam core material to improve the compression and bending properties of the sandwich structure. Vacuum infusion method was used to manufacture the sandwich structure. The bending and compression performance of the structures with and without composite tubes were compared. To measure the bending stiffness and compression properties of the structure, three-point bending and compression tests were conducted according to American Society for Testing and Materials (ASTM) standards. The manufacturing procedure can be easily automated and applied to large and complex shape panels. In addition, a parametric analysis was done to investigate the effect of the number of tubes and the diameter of the tubes on bending and compression stiffness of the structure. According to the test results, the samples including the composite tubes gave six times higher bending stiffness as compared to the samples without the composite tubes. As the diameter of the tubes increased the bending stiffness and the ultimate core shear strength increased. In addition, the structures including 14 mm diameter tubes had higher specific absorbed energy values under compression loading.

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Experimental investigation of compression strength of ventilated corrugated citrus packaging

Packaging Research ◽

10.1515/pacres-2017-0003 ◽

2017 ◽

Vol 2 (1) ◽

pp. 22-27 ◽

Cited By ~ 3

Author(s):

Pankaj B. Pathare ◽

Tarl M. Berry ◽

Umezuruike Linus Opara

Keyword(s):

Compressive Strength ◽

Moisture Content ◽

Compression Strength ◽

Mechanical Performance ◽

Storage Temperature ◽

Citrus Fruit ◽

Storage Condition ◽

Storage Conditions ◽

Airflow Distribution ◽

Postharvest Handling

Abstract Ventilated corrugated paperboard packaging is the most widely type of packaging used in postharvest handling and transportation of fresh horticultural produce, during which the package may be exposed to different environmental conditions. Ventilated packages should be designed in such a way that they can provide uniform airflow distribution without compromising mechanical integrity. This study investigated the effects of different storage conditions (−0.5°C at 90% RH; 4°C at 90% RH, 10° C at 90% RH) on the mechanical performance of two types of ventilated packaging [‘Supervent’ (4.7% vent area) and ‘Standard’ (3.1% vent area)] used for handling citrus fruit. The effects of storage condition on moisture content of package was also studied. Standard packaging showed higher compression strength than supervent packaging, presumably due to less vent area on the package. Maximum compressive strength reduction was found at storage temperature 4°C for both packages. The compressive strength of both packages decreased with increase in moisture content.

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The Effect of Different Thermal Treatment on the Allotropic fcc↔hcp Transformation and Compression Behavior of Polycrystalline Cobalt

Materials ◽

10.3390/ma13245775 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5775

Author(s):

Michal Knapek ◽

Peter Minárik ◽

Patrik Dobroň ◽

Jana Šmilauerová ◽

Mayerling Martinez Celis ◽

...

Keyword(s):

Grain Size ◽

Yield Strength ◽

Performance Optimization ◽

Fracture Strain ◽

Mechanical Performance ◽

Effective Means ◽

Basic Material ◽

Phase Content ◽

Compression Behavior ◽

Fcc Phase

Pure polycrystalline cobalt is systematically thermally treated in order to assess the effect of the microstructure on the compression behavior. Isothermal annealing of the as-drawn material leads to recrystallization and grain growth dependent on the annealing temperature (600–1100 ∘C). Consequently, the yield strength decreases and the fracture strain increases as a function of rising grain size; the content of the residual fcc phase is ~6–11%. Subsequent thermal cycling around the transition temperature is applied to further modify the microstructure, especially in terms of the fcc phase content. With the increasing number of cycles, the grain size further increases and the fraction of the fcc phase significantly drops. At the same time, the values of both the yield strength and fracture strain somewhat decrease. An atypical decrease in the fracture strain as a function of grain size is explained in terms of decreasing fcc phase content; the stress-induced fcc→hcp transformation can accommodate a significant amount of plastic strain. Besides controlling basic material parameters (e.g., grain size and texture), adjusting the content of the fcc phase can thus provide an effective means of mechanical performance optimization with respect to particular applications.

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Finite Elements for Curved Sandwich Beams

Aeronautical Quarterly ◽

10.1017/s0001925900008027 ◽

1977 ◽

Vol 28 (2) ◽

pp. 123-141 ◽

Cited By ~ 5

Author(s):

P J Holt ◽

J P H Webber

Keyword(s):

Finite Elements ◽

Stiffness Matrix ◽

Test Cases ◽

Sandwich Beams ◽

Honeycomb Core ◽

The Core ◽

The Face ◽

Core Thickness ◽

Displacement Approach ◽

Circular Sandwich Ring

SummaryThe formulation of curved finite elements to represent a two-dimensional circular sandwich ring with honeycomb core and laminated faces is investigated. Assumed stress hybrid and equilibrium methods are found to be easier to employ in this case than the displacement approach. Using these methods, an element stiffness matrix is developed. The approximations of membrane faces and an infinite core normal stiffness are then used to develop simpler elements. Test cases show that these assumptions may become invalid, but that they are adequate for most practical cases where the core thickness to radius ratio and the face thickness to core thickness ratio are both low.

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