Multilayer and Fiber Metal Laminate Materials Hydro-Bulging

2018 ◽  
Vol 941 ◽  
pp. 1996-2005
Author(s):  
Ehsan Sherkatghanad ◽  
Li Hui Lang ◽  
Shi Chen Liu
Keyword(s):  
Thickness Distribution ◽  
Single Layer ◽  
Experimental Tests ◽  
Middle Layer ◽  
Composite Fiber ◽  
Advanced Materials ◽  
Carbon Cloth ◽  
Stress Strain ◽  
Aluminum Composite ◽  
Fiber Metal

Advanced materials such as aluminum alloys and composites offer great potential for weight reduction applications in automotive and aerospace vehicles construction. In order to investigate the feasibility of using such materials in the form of laminates, sheet bulging with single-layer aluminum and the aluminum/Composite laminate with the carbon cloth as the middle layer is investigated under uniform liquid pressure conditions. The aluminum sheet stress-strain, wall thickness distribution, carbon fiber radius stress-strain distribution and the effect of die entrance radius etc. are discussed and compared in details. FE results validate that the numerical method can predict the same fracture regions for bulging-blank as observed in experimental tests. Furthermore, the study validates that multi-layer sheet hydro-bulging process with composite fiber as a middle layer is not feasible to form laminates due to rupture of composite fibers near edge regions. Further study is needed to improve the methodology.

The influence of different compositions of fiber metal laminates on the fracture in the semi-solidified stamping forming

2020 ◽  
pp. 105678952095447
Author(s):  
Lei Li ◽  
Lihui Lang ◽  
Blala Hamza ◽  
Sergei Alexandrov ◽  
Shiyue Li
Keyword(s):  
Thickness Distribution ◽  
Process Condition ◽  
Middle Layer ◽  
Forming Limit ◽  
Fiber Metal Laminates ◽  
Specific Strength ◽  
Bonding Performance ◽  
Fiber Deformation ◽  
Fiber Metal ◽  
Small Parts

Fiber metal laminates (FMLs) are widely used in manufacturing due to the high specific strength, fatigue resistance, and lightweight. However, because of the deformation coordination of different layers of FMLs, challenges have been faced in rapid and small part forming. To research the feasibility of the fast forming of small parts using the FMLs, the influence of different compositions of FMLs on the stamping performance under the semi-solidified process condition was investigated, including the outer aluminum layer, the fiber lay-up direction in the middle layer, and the various states of the resin. Based on the results of Finite-element simulation and experiments, the semi-solidified process can improve the forming performance of FMLs by making the thickness distribution of the outer aluminum layers more uniform and preventing excessive fiber deformation. The coordination of fiber lay-up direction and interlayer forces can improve the forming limit height of semi-solidified FMLs. Besides, the fracture position of the cup part is related to the fiber lay-up direction and interfacial bonding performance in FMLs. This study provides necessary guidance for the rapid stamp forming of small parts using FMLs.

scholarly journals Sustainable Wall Solutions Using Foam Concrete and Hemp Composites

2021 ◽  
Vol 25 (1) ◽  
pp. 917-930
Author(s):  
Genadijs Sahmenko ◽  
Maris Sinka ◽  
Eva Namsone ◽  
Aleksandrs Korjakins ◽  
Diana Bajare
Keyword(s):  
Environmental Impact ◽  
Carbon Dioxide Emissions ◽  
High Performance ◽  
Single Layer ◽  
Middle Layer ◽  
Natural Fibre ◽  
Advanced Materials ◽  
High Porosity ◽  
Foam Concrete ◽  
Sandwich Type

Abstract This work is devoted to developing an energy-efficient solution for the external wall and evaluating its environmental impact. Several types of innovative single-layer and sandwich-type wall solutions were analysed and compared. Different constructive and thermal insulation materials were used, including traditional wall materials such as AAC (autoclaved aerated concrete) and normal concrete. Advanced materials, such as high-performance foamed concrete (HPFC) and natural biofibre composites, have been evaluated as an alternative solution. Ultra-light foam concrete was applied as an alternative for polymer-based insulation. The next development was sandwich three-layer wall constructions consisting of foam concrete and natural biofibre composites. A prototype of a wall panel was elaborated with outer layers of high-density bio-composite and a middle layer of high porosity hemp composite. Basic properties of sandwich blocks, such as density and thermal conductivity, were evaluated and compared. The environmental impact of the studied wall systems was analysed using a life-cycle assessment (LCA) to assess carbon dioxide emissions during the production phase of the material. The results show that replacing traditional insulation with bio-based materials has greatly reduced the negative environmental impact of the wall elements. A combination of natural fibre bio-composite and mineral insulating foam makes it possible to obtain an eco-friendly and sustainable sandwich-type wall system.

scholarly journals Kinetics of slow release of nitrogen fertiliser from multi-layered nanofibrous structures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Leila Javazmi ◽  
Anthony Young ◽  
Gavin J. Ash ◽  
Tobias Low
Keyword(s):  
Crop Production ◽  
Slow Release ◽  
New Technology ◽  
Single Layer ◽  
Middle Layer ◽  
Modern Agriculture ◽  
Triple Layer ◽  
Urea Release ◽  
Electrospun Nanofibres ◽  
Kinetics Of

AbstractFertilisers are essential in modern agriculture to enhance plant growth, crop production and product quality. Recent research has focused on the development of delivery systems designed to prolong fertiliser release. This study introduces a new technology to encapsulate and release molecules of fertilisers by using multi-layered electrospun nanofibre as a carrier. Single-layer poly L-lactic acid (PLLA) nanofibres loaded with urea were fabricated using electrospinning. Triple-layer nanofibrous structures were produced by electrospinning polyhydroxybutyrate (PHB) nanofibres as external layers with PLLA nanofibres impregnated with urea fertiliser as the middle layer. Scanning electron microscopy (SEM) and Fourier transform infrared spectrophotometry (FTIR) were employed to characterize the morphology of electrospun nanofibres. Urea release dynamic was analysed using a total nitrogen instrument (TNM-1). The results indicated that triple-layered urea-impregnated nanofibrous structures led to lower initial rate of nitrogen release and slower release rate of cumulative nitrogen which extended for more than three months. It is concluded that triple-layer nanofibrous structures have the potential for slow release delivery of fertilisers.

scholarly journals Numerical Analysis of the Perforated Steel Sheets Under Uni-Axial Tensile Force

Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 632 ◽  
Author(s):  
Ahmed M. Sayed
Keyword(s):  
Load Capacity ◽  
Tensile Force ◽  
Three Dimensional ◽  
Tensile Load ◽  
Experimental Tests ◽  
Strain Engineering ◽  
Uniaxial Tensile ◽  
Fe Model ◽  
Stress Strain ◽  
Steel Sheets

The perforated steel sheets have many uses, so they should be studied under the influence of the uniaxial tensile load. The presence of these holes in the steel sheets certainly affects the mechanical properties. This paper aims at studying the behavior of the stress-strain engineering relationships of the perforated steel sheets. To achieve this, the three-dimensional finite element (FE) model is mainly designed to investigate the effect of this condition. Experimental tests were carried out on solid specimens to be used in the test of model accuracy of the FE simulation. Simulation testing shows that the FE modeling revealed the ability to calculate the stress-strain engineering relationships of perforated steel sheets. It can be concluded that the effect of a perforated rhombus shape is greater than the others, and perforated square shape has no effect on the stress-strain engineering relationships. The efficiency of the perforated staggered or linearly distribution shapes with the actual net area on the applied loads has the opposite effect, as it reduces the load capacity for all types of perforated shapes. Despite the decrease in load capacity, it improves the properties of the steel sheets.

scholarly journals Dynamics of Polysaccharides and Neutral Lipids during Anther Development in Castor (Ricinus communis)

2015 ◽  
Vol 140 (4) ◽  
pp. 356-361 ◽  
Author(s):  
Dongmei Wei ◽  
Huimin Xu ◽  
Ruili Li
Keyword(s):  
Neutral Lipids ◽  
Ricinus Communis ◽  
Starch Content ◽  
Single Layer ◽  
Pollen Grains ◽  
Middle Layer ◽  
Anther Development ◽  
Anther Wall ◽  
Starch Grains ◽  
Tapetal Cells

Anthers contain starch and neutral lipids, which have key roles in microspore ontogeny and gametophyte development. In this study, we observed the dynamic changes in starch and neutral lipids in the anther developmental processes of castor (Ricinus communis) by cytochemical methods. Starch grains and neutral lipids presented a regular dynamic distribution during anther development. In young anthers, some neutral lipids accumulated in sporogenous cells, whereas neutral lipids disappeared with microspore growth. At the late microspore stage, starch grains began to accumulate in microspores, and the starch content of bicellular pollen significantly increased after microspore mitosis. At anthesis, starch grains and neutral lipids accumulated in the mature pollen grains. Visible changes occurred in anther wall cells. The epidermis, middle layer, and tapetum were degenerated, and only a single layer of endothecium remained at anthesis. The dynamic variation of starch grains and neutral lipids in tapetal cells was consistent with the changes in microspores and pollen during anther development. All these findings demonstrated that tapetal cells directly interacted with the developing gametophytes. The tapetal cells play an important role in supplying nutritional substances for microspore absorption. Moreover, the endothecium protects the pollen and contributes to anther dehiscence. The results of this study provide a foundation for the further research on sexual reproduction in angiosperms.

scholarly journals Some advantages of three-layer medium-density fibreboard as compared to the traditional single-layer one

2019 ◽  
Vol 65 (1) ◽  
Author(s):  
Turgay Akbulut ◽  
Nadir Ayrilmis
Keyword(s):  
Bond Strength ◽  
Internal Bond ◽  
Single Layer ◽  
Middle Layer ◽  
Resin Content ◽  
Internal Bond Strength ◽  
Medium Density ◽  
Medium Density Fibreboard ◽  
Uf Resin ◽  
Layer Medium

Abstract The aim of the study was to develop three-layer medium-density fibreboard (MDF) manufacture by adding the coarse fibres in the middle layer, like three-layer particleboard. The liquid urea–formaldehyde (UF) resin was reduced from 10.5 to 6.5 wt% in the middle layer of the MDFs. The UF resin content was kept constant at 10 wt% in the surface layers of all the MDFs. Moreover, the average density of MDFs was decreased from 730 to 650 kg/m3. The internal bond strength of three-layer MDFs decreased with decreasing UF resin content (10.5 to 8.5 wt%) in the middle layer. However, the decreases in the internal bond strength were statistically not significant. The internal bond strength values of the MDFs having density between 730 and 675 kg/m3 did not show significant differences. The cost savings of the resin were 20% when the amount of resin was reduced from 10.5 to 8.5 wt%. Three-layer MDFs had lower resin consumption at lower densities over traditional single-layer MDFs produced in the same plant with the same material components without decreasing their technological properties. In conclusion, it can be said that three-layer MDF could be produced at a lower cost than traditional single-layer MDF.

scholarly journals Numerical Study on Crack Distributions of the Single-Layer Building under Seismic Waves

Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-16
Author(s):  
Fenghui Dong ◽  
Zhipeng Zhong ◽  
Jin Cheng
Keyword(s):  
Seismic Waves ◽  
Numerical Study ◽  
Single Layer ◽  
Experimental Tests ◽  
Masonry Structure ◽  
Original Model ◽  
Dynamic Responses ◽  
Masonry Structures ◽  
Reinforced Masonry ◽  
Longitudinal Cracks

This paper conducts a numerical simulation of the antiseismic performance for single-layer masonry structures, completes a study on crack distributions and detailed characteristics of masonry structures, and finally verifies the correctness of the numerical model by experimental tests. This paper also provides a reinforced proposal to improve the antiseismic performance of single-layer masonry structures. Results prove that the original model suffers more serious damage than the reinforced model; in particular, longitudinal cracks appear on bottoms of two longitudinal walls in the original model, while these cracks appear later in the reinforced model; a lot of cracks appear on the door hole of the original model, and no crack appears in the reinforced model till the end of seismic waves; seismic damage of walls in the reinforced model is obviously lighter than that in the original model; dynamic responses at all observed points of the reinforced masonry are obviously less than those of the original model. Strains at all positions of the reinforced model are obviously smaller than those of the original model. From macroscopic and microscopic perspectives, the computational results prove that the reinforced proposal proposed in this paper can effectively improve the antiseismic performance of the masonry structure.

scholarly journals Assessment of the load capacity of the anchorage system connecting the textured layer with the structural wall of large slab buildings in the lights of experimental research and FEM analysis

2018 ◽  
Vol 174 ◽  
pp. 03016
Author(s):  
Jerzy K. Szlendak ◽  
Agnieszka Jablonska-Krysiewicz ◽  
Dariusz Tomaszewicz
Keyword(s):  
Load Capacity ◽  
Single Layer ◽  
Fem Analysis ◽  
Experimental Tests ◽  
3D Models ◽  
Elastic Model ◽  
Structural Wall ◽  
Linear Elastic ◽  
Test Elements ◽  
Stainless Steel Screws

The goal of the article is to compare the results obtained from experimental tests of a new type of anchoring, connecting the texture layer with the structural layer in external wall elements, used in large-panel construction with the results from FEM analysis. Two types of samples were subjected to experimental tests: single-layer uniform concrete and three-layer concrete with embedded point anchors and analogous samples with glued anchors. The test elements used C 12/15 and C 30/37 concrete, 12 mm diameter anchors, made of steel corresponding to the grade of stainless steel screws class 5.8, Sika Anchorfix-1 resin and XPS polystyrene. As for the three-layer samples, when testing, two forces were applied: tearing and shearing due to the detachment of the textured layer. The ANSYS program was used for numerical modelling of the analyzed samples. 3D models were built in which solid elements were used. For steel anchors, the material characteristics were taken as a two-line elasticplastic reinforcement. The Drucker-Prager model was used in the concrete elements, the linear-elastic model was adopted for the resin, and the brittle model according to the linear-elastic fracture mechanics for the polystyrene.

Multi-Axial Failure of Ceramic Matrix Composite Fiber Tows

2011 ◽  
Vol 78 (3) ◽  
Author(s):  
M. Blacklock ◽  
D. R. Hayhurst
Keyword(s):  
Axial Stress ◽  
Ceramic Matrix Composite ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Composite Fiber ◽  
Woven Composites ◽  
Matrix Composites ◽  
Stress Strain ◽  
Fiber Failure ◽  
Stressed Region

This paper considers the multi-axial stress-strain-failure response of two commercially woven ceramic matrix composites. The different failure mechanisms of uni-axially stressed tows and woven composites are addressed. A model is postulated in which the local transverse and shear stressing, arising from the weave, instantaneously deactivate wake debonding and fiber pullout and initiates dynamic fiber failure; hence, triggering catastrophic failure of the axially stressed region of the tow. The model is shown to predict experimentally measured stress-strain-failure results for the woven composites considered. Simple stress-strain-failure models are also proposed for tows subjected to axial-transverse and axial-shear loadings, but due to the lack of experimental data they have not been validated.

Sign in / Sign up

Export Citation Format

Share Document