Laser-based additively manufactured bio-inspired crashworthy structure: Energy absorption and collapse behaviour under static and dynamic loadings

Ferrocement is one of the structural materials, widely used due to its advantages from its particular behavior such as mechanical properties, and impact strength. This paper deals with the impact studies and energy absorption properties of ferrocement slabs. For these studies, 11 different ferrocement slabs of size 50 mm X 500 mm X 25 mm were cast with alteration in the combinations of mesh layers and test results are analyzed to find the different crack patterns .The test specimens were loaded by 3.10 kg under its height 1.20 m in the center of plates. The ferrocement plates were divided into 4 groups reinforced with steel mesh, steel mesh with steel bars, percentage of rubber and fiber. The impact energy at initial cracking stage and at failure was determined for all the slabs. Results of reinforced ferrocement plates emphasized that increasing the number of the steel mesh layers in the ferrocement forms increases the first cracking load, ultimate load and energy absorption. Using steel bars with steel meshes led to higher energy absorption than that obtained when using mild steel bars only. Using rubber and fiber achieved high impact energy.

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Magnesium Alloys: An Alternative for Aluminium in Structural Applications

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.168-170.1631 ◽

2010 ◽

Vol 168-170 ◽

pp. 1631-1635 ◽

Cited By ~ 3

Author(s):

Dong Wei Shu ◽

Iram Raza Ahmad

Keyword(s):

Energy Absorption ◽

Magnesium Alloys ◽

Industrial Development ◽

Dynamic Loads ◽

Specific Strength ◽

Body Armour ◽

Structural Applications ◽

Dynamic Loadings ◽

Dynamic Loading Conditions ◽

Significant Mass

There is a fast moving trend towards using lightweight materials in automotive, aerospace, building and construction, body armour and protection, sports and leisure goods. The dynamic industrial development puts higher demands for lighter and yet stronger materials. Magnesium alloys potentially met the present demands for lighter and reliable construction. With comparable specific stiffness, higher specific strength and energy absorption magnesium alloys have the potential to replace steel and aluminum alloys. Magnesium alloys are very useful for applications where materials are subjected to variable or dynamic loads such as crash events in vehicles and planes, buildings and structures against projectiles penetration etc. To know the materials’ response to impacts and their resistance to blast and shock, it is necessary to understand their behaviour under static as well as dynamic conditions. In current study, magnesium alloys AZ91D and AM50 have been studied at dynamic loading conditions and compared with aluminum alloy AA6061-T6. With significant mass saving, higher specific properties and higher energy absorption under dynamic loadings, magnesium alloys are promising candidates to replace conventional materials not only aluminum but steel as well in structural applications.

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Energy absorption rate of composite tube as a function of stacking sequence using finite element method

Science and Engineering of Composite Materials ◽

10.1515/secm-2012-0171 ◽

2015 ◽

Vol 22 (6) ◽

Author(s):

Ramin Amid ◽

Zouheir Fawaz ◽

Hamid Ghaemi

Keyword(s):

Energy Absorption ◽

Absorption Rate ◽

Impact Load ◽

Load Condition ◽

Failure Criteria ◽

Energy Dissipation Rate ◽

Stacking Sequence ◽

Energy Transfer Rate ◽

Material Parameters ◽

Dynamic Loadings

AbstractNumerical investigations were performed on a series of laminated composites when subjected to dynamic loadings, in order to determine their energy absorption rate and dissipating energy during impact. The details of numerical modeling, contact analysis, material parameters, and failure criteria were explained and discussed. We aimed to determine the energy absorption rate of various quasi-isotropic lay-ups when subjected to the dynamic loadings, and found that energy dissipation rate varied depending on stacking sequence. In this investigation, we studied how the energy absorption rate and the peak impact load change as a result of changing stacking sequence, with all stacking sequences being quasi-isotropic. Using a constant impacting mass and varied impacting speeds, we found that stacking sequence can significantly control the energy transfer rate or energy absorption rate under dynamic load condition.

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Impact of the Foamed Aluminum-Filled Structures

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.44-47.372 ◽

2010 ◽

Vol 44-47 ◽

pp. 372-377

Author(s):

Zhong Guo Zhang ◽

Yu Zhou Sun ◽

Bin Gao

Keyword(s):

Energy Absorption ◽

Shell Thickness ◽

Aluminum Foam ◽

Load Capacity ◽

Absorption Capacity ◽

Steel Shell ◽

Absorption Characteristic ◽

Dynamic Loadings ◽

Energy Absorbing ◽

The Impact

The carrying capacity and energy absorption characteristic of foamed aluminum (or aluminum foam), fabricated by melt foaming technique, are limited due to the lower strength of aluminum. The typical anti-vibration energy absorbing structures are designed as foamed aluminum-filled or sandwich structures. The deformation and absorption characteristics of foamed aluminum-filled structures subjected to impact loadings are analyzed using experimental and numerical methods in this work. The analysis shows that the steel shell of the combinative structure subjected to dynamic loadings dominates during energy absorption. The energy absorption capacity and initial instability loading increase as impact velocity increase and as increasing shell thickness duo to the interaction between steel shell and aluminum foam. The impact mass within the range of 100kg influences weakly on peak instability loading. Since the steel shell is the dominating part of load capacity and energy absorption, the reasonable design, taking into account of foam density and shell thickness and taking full advantage of interaction between steel shell and aluminum foam, should be adopted to increase the energy absorption characteristic of foam-filled structures.

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