scholarly journals A New Type of Hierarchical Honeycomb In-Plane Impact Study

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1917
Author(s):  
Hang Song ◽  
Chenyang Zhang ◽  
Pengyu Wang ◽  
Lingzhi Meng ◽  
Zhenqing Wang
Keyword(s):  
Impact Resistance ◽  
Second Order ◽  
Failure Stress ◽  
Sound Insulation ◽  
Specific Strength ◽  
Element Simulation ◽  
New Type ◽  
Insulation Effect ◽  
Strength And Stiffness ◽  
Double Arrow

Honeycomb materials have low density, high specific strength and stiffness, impact resistance, and good sound insulation effect, and therefore are widely used in aerospace, automobile, and ship field applications. In this paper, we study the in-plane impact response of a second-order hierarchical honeycomb (SHH) material. Its main structure is a hexagonal honeycomb, and the substructure is composed of an augmented double arrow honeycomb (ADAH) negative Poisson’s ratio unit. Through a finite element simulation, the failure stress of an hierarchical honeycomb in two directions of quasi-static crushing and dynamic crushing was analyzed; the failure stress of the hierarchical honeycomb under different densities, different speeds, and different substructures was discussed; and the theoretical failure stress was verified. The numerical analysis results show that a second-order hierarchical honeycomb (SHH) has better collapse stress than a first-order regular hexagonal honeycomb (FHH) and an augmented double arrow honeycomb (ADAH).

Biaxial weft-knitted fabrics as composite reinforcements: A review

2016 ◽  
Vol 46 (7) ◽  
pp. 1439-1473 ◽  
Author(s):  
Hossein Hasani ◽  
Sanaz Hassanzadeh ◽  
Mohammad Javad Abghary ◽  
Elahe Omrani
Keyword(s):  
Mechanical Properties ◽  
Volume Fraction ◽  
Impact Resistance ◽  
High Energy ◽  
Fiber Volume ◽  
Technical Application ◽  
Knitted Fabrics ◽  
Specific Strength ◽  
Strength And Stiffness ◽  
Composite Reinforcements

Textile products are considered as an acceptable alternative for commonly used composite reinforcement due to their lightweight as well as relatively high specific strength and stiffness. Among the variety of textile structures which could be employed in composite manufacturing, the role of weft-knitted fabrics is almost very limited. This is because employing the weft-knitting technology would provide such structures with inferior mechanical properties due to their highly looped construction as well as low fiber volume fraction. But on other hand, it is important to be noted that some advantages such as high energy absorption, good impact resistance, and formability of knitted structures made the researchers to focus on investigating different methods by which the inferior mechanical properties of ordinary weft-knitted fabrics could be improved. Inserting the reinforcing yarns through the warp and weft direction of the knitted fabrics is considered as one of the effective solution for improving their mechanical behavior which eventually leads to a high potential product called as biaxial weft-knitted fabrics. In this literature, it is aimed to review different aspects of novel designed biaxial weft-knitted fabrics which could be suitable for a broad area of technical application such as composite reinforcements.

Progress in Foldcore Sandwich Manufacturing and Application

2022 ◽  
Vol 905 ◽  
pp. 246-253
Author(s):  
Hong Wei Tian ◽  
Hai Feng Chang ◽  
Hong Jun Ye
Keyword(s):  
Sandwich Structure ◽  
Thermal Protection ◽  
Three Dimensional ◽  
Sound Insulation ◽  
Functional Requirements ◽  
Optimization Scheme ◽  
Main Research ◽  
Specific Strength ◽  
Two Dimensional Materials ◽  
New Type

The sandwich structure with foldcore is a new type of structural material with light weight, high specific strength, high specific rigidity and multi-functional potential, which is connected with each other in core space, this kind of three dimensional structures can be formed by folding based on two dimensional materials. The main research achievements and characteristics of sandwich structure with foldcore in recent years are summarized and analyzed according to the lightweight and multi-functional requirements of aircraft structure in this paper. The configuration optimization scheme and fabrication process of the sandwich structure with foldcore are described. Moreover, the research status of multi-function of the sandwich structure with foldcore are summarized, including sound insulation, thermal protection, stealth performance of the structure, etc.

A New Periodic Cellular Metal With Kagome Trusses and Its Performance

Aerospace ◽  
2006 ◽  
Author(s):  
Yong-Hyun Lee ◽  
Ji-Eun Choi ◽  
Ki-Ju Kang
Keyword(s):  
Raw Materials ◽  
Future Market ◽  
New Materials ◽  
Specific Strength ◽  
Cellular Metal ◽  
High Specific Strength ◽  
New Type ◽  
Strength And Stiffness ◽  
Metal Wires ◽  
Very High

Periodic cellular metals (PCM), especially truss PCM's seem promising as new materials in 21 century. Various works have been performed for the mechanical and thermal performance. However, only a number of papers have been published regarding fabrication techniques of PCM, even though the techniques should determine whether PCM's is survived in the future market, or not. In this work a new type of PCM with Kagome trusses is presented. Continuous metal wires as the raw materials are assembled in six directions with least deflection, which gives very high specific strength and stiffness. The mechanical behavior under compression and bending of hand-made specimens is presented. Also, the benefits and features are discussed.

Structural Behavior of FRP Lighting Pole System

2010 ◽  
Vol 654-656 ◽  
pp. 1034-1037
Author(s):  
Sun Hee Kim ◽  
Gi Nam Kim ◽  
Soon Jung Hong ◽  
Chang Won Kim ◽  
Won Sup Jang ◽  
...  
Keyword(s):  
Construction Materials ◽  
Structural Behavior ◽  
Specific Strength ◽  
Construction Market ◽  
High Chemical Resistance ◽  
Manufacturing Procedure ◽  
New Type ◽  
Strength And Stiffness ◽  
Electro Magnetic ◽  
Pole System

Street lighting system is an essential structure for the safety of traffic. Most of the lighting pole is made of steel and it is vulnerable to corrosion due to its hazardous surrounding environment. To mitigate such corrosion problems, stainless steel and iron steel are usually adopted, but they are also usually manufactured by hand, so it is not economical. Therefore, to overcome such problems new type FRP lighting pole is proposed. In recent years, FRP materials in the construction market are popularly utilized as an alternative for conventional construction materials. FRP material is known to have many advantages such as high chemical resistance, electro-magnetic transparency, high specific strength and stiffness, etc. In this paper, structural behavior of FRP lighting pole is compared with that of conventional lighting pole structures and we proposed the cross-section configuration of the FRP lighting pole with details on the manufacturing procedure.

scholarly journals Materials for Automotive Lightweighting

2019 ◽  
Vol 49 (1) ◽  
pp. 327-359 ◽  
Author(s):  
Alan Taub ◽  
Emmanuel De Moor ◽  
Alan Luo ◽  
David K. Matlock ◽  
John G. Speer ◽  
...  
Keyword(s):  
Galvanic Corrosion ◽  
Low Carbon Steel ◽  
High Strength Steels ◽  
High Strength ◽  
Low Carbon ◽  
New Materials ◽  
Specific Strength ◽  
Advanced High Strength Steels ◽  
Strength And Stiffness ◽  
The Cost

Reducing the weight of automobiles is a major contributor to increased fuel economy. The baseline materials for vehicle construction, low-carbon steel and cast iron, are being replaced by materials with higher specific strength and stiffness: advanced high-strength steels, aluminum, magnesium, and polymer composites. The key challenge is to reduce the cost of manufacturing structures with these new materials. Maximizing the weight reduction requires optimized designs utilizing multimaterials in various forms. This use of mixed materials presents additional challenges in joining and preventing galvanic corrosion.

Recent Advances in Development and Processing of Titanium Aluminide Alloys

2000 ◽  
Vol 646 ◽  
Author(s):  
Fritz Appel ◽  
Helmut Clemens ◽  
Michael Oehring
Keyword(s):  
High Temperature ◽  
Titanium Aluminide ◽  
Titanium Aluminides ◽  
Environmental Stability ◽  
Physical Metallurgy ◽  
Specific Strength ◽  
Wide Range ◽  
Structural Applications ◽  
Strength And Stiffness ◽  
Nickel Base

ABSTRACTIntermetallic titanium aluminides are one of the few classes of emerging materials that have the potential to be used in demanding high-temperature structural applications whenever specific strength and stiffness are of major concern. However, in order to effectively replace the heavier nickel-base superalloys currently in use, titanium aluminides must combine a wide range of mechanical property capabilities. Advanced alloy designs are tailored for strength, toughness, creep resistance, and environmental stability. Some of these concerns are addressed in the present paper through specific comments on the physical metallurgy and technology of gamma TiAl-base alloys. Particular emphasis is placed on recent developments of TiAl alloys with enhanced high-temperature capability.

scholarly journals A new type of second-order cosmological Lagrangians

2013 ◽  
Vol 19 (4) ◽  
pp. 288-291 ◽  
Author(s):  
P. Tretyakov
Keyword(s):  
Second Order ◽  
New Type

Analytical higher-order-theories for noise reduction analysis of viscoelastic composite multilayered shells

2021 ◽  
pp. 095440622098233
Author(s):  
A Alaimo ◽  
C Orlando ◽  
S Valvano
Keyword(s):  
Sound Transmission ◽  
Higher Order ◽  
Sound Insulation ◽  
Viscoelastic Layer ◽  
Multilayered Structures ◽  
Viscoelastic Composite ◽  
Damping Behavior ◽  
Shell Models ◽  
Composite Layers ◽  
Insulation Effect

The noise transmission of aeronautical panels is an important phase of the design process of an airplane. In this work an analytical Navier-type solution, based on higher-order layer-wise shell models, is proposed for the analysis of the sound insulation of laminated panels. The considered multilayered structures are laminated with cross-ply composite layers embedded with interlaminar viscoelastic sheets. The use of the soft interlayers permits to have a passive insulation effect in the study of the sound transmission. In order to take into account the frequency depedent properties of a realistic viscoelastic layer, the damping behavior is modeled through a fractional derivative Zener model. The Rayleigh integral method is used to extrapolate the acoustic indicators for the sound transmission analysis. Some results are presented to validate the efficiency of the present approach, comparing the present solutions with others taken from the literature.

scholarly journals Effects of plies orientations and initial geometric imperfections on buckling strength of a composite stiffened panel

2018 ◽  
Vol 191 ◽  
pp. 00008
Author(s):  
Ikram Feddal ◽  
Abdellatif Khamlichi ◽  
Koutaiba Ameziane
Keyword(s):  
Stiffened Panel ◽  
Buckling Mode ◽  
Element Analysis ◽  
Geometric Imperfections ◽  
Stiffened Panels ◽  
Specific Strength ◽  
Euler Buckling ◽  
Buckling Behavior ◽  
Composite Stiffened Panel ◽  
Strength And Stiffness

The use of composite stiffened panels is common in several activities such as aerospace, marine and civil engineering. The biggest advantage of the composite materials is their high specific strength and stiffness ratios, coupled with weight reduction compared to conventional materials. However, any structural system may reach its limit and buckle under extreme circumstances by a progressive local failure of components. Moreover, stiffened panels are usually assembled from elementary parts. This affects the geometric as well as the material properties resulting in a considerable sensitivity to buckling phenomenon. In this work, the buckling behavior of a composite stiffened panel made from carbon Epoxy Prepregs is studied by using the finite element analysis under Abaqus software package. Different plies orientations sets were considered. The initial distributed geometric imperfections were modeled by means of the first Euler buckling mode. The nonlinear Riks method of analysis provided by Abaqus was applied. This method enables to predict more consistently unstable geometrically nonlinear induced collapse of a structure by detecting potential limit points during the loading history. It was found that plies orientations of the composite and the presence of geometric imperfections have huge influence on the strength resistance.

Sign in / Sign up

Export Citation Format

Share Document