EXPERIMENTAL INVESTIGATION ON THE MAXIMUM AXIAL FORCE OF AN ALUMINUM SQUARE COLUMN

2015 ◽  
Vol 76 (11) ◽  
Author(s):  
Hafizi Lukman ◽  
Amir Radzi Ab. Ghani ◽  
Hafizan Hashim ◽  
Mohd Adzureen Bin Zulkefli ◽  
M Mahat

Energy absorption is one of the characteristics that must be included especially in transportation systems. This property dissipates kinetic energy during collisions. Normally, industries use thin wall structures because of their ease of fabrication, high performance, and low cost. This study determines the first peak force and energy absorption of an aluminum square column. The square columns prepared with various design patterns exhibited different results. The designs showed favorable results in terms of increasing the specific energy absorption and reducing the initial peak force. To achieve the project objective, this project conducted two types of analyses using INSTRON 3382 for the experimental analysis.

2019 ◽  
Vol 10 (1) ◽  
pp. 133-143 ◽  
Author(s):  
Jiayao Ma ◽  
Huaping Dai ◽  
Mengyan Shi ◽  
Lin Yuan ◽  
Yan Chen ◽  
...  

Abstract. Thin-walled tubes are widely used as energy absorption devices for their low cost and high manufacturability. Introduction of the origami technique enables the tube to follow a pre-determined failure mode and to improve its energy absorption efficiency. This paper examines the energy absorption characteristics of the origami crash box under quasi-static axial crushing. Both experimental and numerical results show that the origami pattern develops a diamond-shaped mode, bringing a reduction in initial peak force and a significant increase in energy absorption compared to the conventional hexagonal tube. The sensitivity of its energy absorption performance to various parameters is studied, and it is shown to achieve 68.29 % increase in the specific energy absorption and 13.91 % reduction in the initial peak force in the optimal case. Furthermore, an analytical solution is presented for the energy absorption, which achieves reasonable agreement with the numerical results.


Author(s):  
Mengyan Shi ◽  
Jiayao Ma ◽  
Yan Chen ◽  
Zhong You

Thin-walled tubes as energy absorption devices are widely in use for their low cost and high manufacturability. Employing origami technique on a tube enables induction of a predetermined failure mode so as to improve its energy absorption efficiency. Here we study the energy absorption of a hexagonal tubular device named the origami crash box numerically and theoretically. Numerical simulations of the quasi-static axial crushing show that the pattern triggers a diamond-shaped mode, leading to a substantial increase in energy absorption and reduction in initial peak force. The effects of geometric parameters on the performance of the origami crash box are also investigated through a parametric study. Furthermore, a theoretical study on the deformation mode and energy absorption of the origami crash box is carried out, and a good match with numerical results is obtained. The origami crash box shows great promise in the design of energy absorption devices.


2012 ◽  
Vol 192-193 ◽  
pp. 551-555
Author(s):  
Zhi Feng Zhang ◽  
Jun Xu ◽  
Yue Long Bai ◽  
Ya Bao Wang

Semisolid forging process, characterized by short process, near-net shape, low cost, and high performance, is increasingly playing an important role in lightweighting transportation systems for light metals. In this study, semisolid forging process for hypereutectic Al-Si alloy, as a substitute for nodular cast iron, was applied in producing automobile AC compressor components. The results showed that hypereutectic Al-Si alloy swash plate thixo-forged had higher strength than nodular cast iron one by optimizing forming process parameters.


2009 ◽  
Vol 76 (4) ◽  
Author(s):  
S. B. Bodlani ◽  
S. Chung Kim Yuen ◽  
G. N. Nurick

This two-part article reports the results of experimental and numerical works conducted on the energy absorption characteristics of thin-walled square tubes with multiple circular hole discontinuities. Part I presents the experimental tests in which dynamic and quasistatic axial crushings are performed. The mild steel tubes are 350 mm in length, 50 mm wide, and 1.5 mm thick. Circular hole discontinuities, 17 mm in diameter, are laterally drilled on two or all four opposing walls of the tube to form opposing hole pairs. The total number of holes varies from 2 to 10. The results indicate that the introduction of holes decreases the initial peak force but an increase in the number of holes beyond 2 holes per side does not further significantly decrease the initial peak force. The findings show that strategic positioning of holes triggers progressive collapse hence improving energy absorption. The results also indicate that the presence of holes may at times disrupt the formation of lobes thus compromising the energy absorption capacity of the tube. In Part II, the finite element package ABAQUS/EXPLICIT version 6.4–6 is used to model the dynamic axial crushing of the tubes and to investigate the action of the holes during dynamic loading at an impact velocity of 8 m/s.


2013 ◽  
Vol 275-277 ◽  
pp. 792-798
Author(s):  
Amir Radzi Ab Ghani ◽  
Hafizi Lukman ◽  
Hafizan Hashim

Thin-walled tubes are generally used as impact energy absorber in various application due to their ease of fabrication and installation, high energy absorption capacity and long stroke. However, the main drawback of plain tube is the high initial peak force. A concentric plunger in the form of tapered block is proposed to overcome this shortcoming while at the same time, improving the impact performance. Static and dynamic axial crushing were performed to determine the initial peak force (IPF), crush force efficiency (CFE) and specific energy absorption (SEA) for the concentric plunger with various taper angles. It was found that the concentric plunger affected the tube impact response. Comparison with plain circular tube was carried out and it was found that the concentric plunger improved the impact response of the tube especially in term of initial peak force.


2017 ◽  
Vol 744 ◽  
pp. 317-321 ◽  
Author(s):  
Rafea Dakhil Hussein ◽  
Dong Ruan ◽  
Guo Xing Lu ◽  
Akshay Kumar

The aim of this study is to find the best platen with blades as a new energy dissipating mechanism that causes considerably damage to CFRP/aluminium tubes. Specially designed and manufactured platens with five different cutting blade profiles were used to simultaneously cut and crush square CFRP tubes and aluminium sheet-wrapped CFRP tubes. The platens with blades were evaluated in terms of the deformation mode, mean crushing force, energy absorption and specific energy absorption of tubes. Experimental results showed that tubes cut and crushed by the platen with 45o inclined blades had the best crushing performance and exhibited a more stable deformation mode compared with those for tubes cut and crushed by other platens with different blade profiles. The platens with blades acted as trigger mechanisms that minimise the initial peak crushing force and maximise the energy absorption of tubes compared with tubes crushed by flat loading platens.


2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Felix Dionisius ◽  
Jos Istiyanto ◽  
Tito Endramawan ◽  
Andri Andri

Crashworthiness is an ability of a vehicle structure in order to reduce injury when occurred in collision. Crashworthiness criteria are peak force (Fmax), specific energy absorption (SEA), and crush force efficiency (CFE). The part of structure of vehicle in crashworthiness is front rail which is generally tube as thin walled structure. The aim was to know the best design in thin walled square tube as specimen by variance of crush initiator which arranged holes 3 mm of diameter in shaping stripe with 4 holes, then added graded holes in parallelogram to trigon. This research used compression experiment method under quasi static loading with 30 mm/minute of actuator velocity. Optimum design was done by using Multi Criteria Decision Making (MCDM) with Simple Additive Weighting (SAW) modelling. This research presents that specimen with trigon of crush initiator is the best design with 0.98 of decision score in which crashworthiness criteria for peak force, specific energy absorption and crush force efficiency are 19193.81 N; 5100.93 J/kg; and 46.44%.


Author(s):  
Sean Jenson ◽  
Eboreime Ohioma ◽  
Muhammad Ali ◽  
Khairul Alam

Abstract Thin wall structures are primarily deployed in automotive chassis to increase the energy absorption capacity of the automobiles in the event of an accident. Researchers have delved into developing lighter structures for improving automobiles’ fuel efficiency with a challenge of maintaining or preferably exceeding the energy absorption properties of the structure. In this study, the work presented is a continuation of research conducted on exploring the effects of the introduction of cellular core in tubular structures under axial compressive loading. The crushing response of cellular core cross tube was numerically studied using ABAQUS/Explicit module. The characteristics such as deformation or collapsing modes, crushing/ reactive force, locking strain, energy curves, and specific energy absorbed were studied. The cellular core cross tube shows significant potential for reducing the weight of automobile structure while giving positive indication towards enhancing the specific energy absorption capacity.


Author(s):  
Xiangyu You ◽  
Chengcong Ye ◽  
Ping Guo

Three-dimensional (3D) printing of microscale structures with high resolution (sub-micron) and low cost is still a challenging work for the existing 3D printing techniques. Here we report a direct writing process via near-field melt electrospinning to achieve microscale printing of single filament wall structures. The process allows continuous direct writing due to the linear and stable jet trajectory in the electric near-field. The layer-by-later stacking of fibers, or self-assembly effect, is attributed to the attraction force from the molten deposited fibers and accumulated negative charges. We demonstrated successful printing of various 3D thin wall structures (freestanding single walls, double walls, annular walls, star-shaped structures, and curved wall structures) with a minimal wall thickness less than 5 μm. By optimizing the process parameters of near-field melt electrospinning (electric field strength, collector moving speed, and needle-to-collector distance), ultrafine poly (ε-caprolactone) (PCL) fibers have been stably generated and precisely stacked and fused into 3D thin-wall structures with an aspect ratio of more than 60. It is envisioned that the near-field melt electrospinning can be transformed into a viable high-resolution and low-cost microscale 3D printing technology.


Author(s):  
Degao Hou ◽  
Yan Chen ◽  
Jiayao Ma ◽  
Zhong You

Thin-walled tubes are widely used as energy absorption devices in automobiles, designed to protect the costly structures and people inside during an impact event through plastic deformation. They show excellent performance under axial loading in terms of weight efficiency, stroke distance and total energy absorption, but also have the disadvantage that the crushing force is not uniform during deformation process, especially with the existence of a high initial peak force. Recently, pattern design on tubular structures has received increasing attention. It has been found that, if the surface of a tube is pre-folded according to an origami pattern, the collapse mode of the tube can be altered, leading to changes in energy absorption performance. In this paper, we present a series of origami patterned tubes with a kite-shape pattern that is constructed by joining two pieces of Miura-ori. First of all, the geometry of the pattern is presented. We develop a theoretical model to predict the energy absorption associated with the axial crushing of the patterned tubes and derive a mathematical formula to calculate the mean crushing force accordingly. Secondly, a family of origami tubes with various profiles are designed, and their performances subjected to quasi-static axial crushing are numerically investigated. A parametric study is also conducted to establish the relationship between the pre-folded angle of the pattern and the initial peak force as well as the mean crushing force. Numerical results show that introducing patterns to thin-walled tubes offers three advantages in comparison with conventional tubes, i.e., a lower initial peak force, a more uniform crushing load, and a stable and repeatable collapse mode. A 36.0% increase in specific energy absorption and 67.2% reduction in initial peak force is achieved in the optimum case. The new origami patterned tubes show great promise as energy absorption devices.


Sign in / Sign up

Export Citation Format

Share Document