Experimental investigation on the cross-tensile properties of tubular rivet-reinforced joints

2021 ◽  
pp. 095440892110436
Author(s):  
Xiaoqiang Ren ◽  
Chao Chen ◽  
Hao Peng ◽  
Xiangkun Ran ◽  
Denglin Qin
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Energy Absorption ◽  
Wall Thickness ◽  
Absorption Capacity ◽  
Strength Performance ◽  
Static Tensile ◽  
Absorption Performance ◽  
The Cross ◽  
Interlock Structure

To decrease the exterior protrusion height and improve the tensile strength of the clinched joint, a rivet-reinforcing method was implemented on the clinched joint in this study. Solid rivets and tubular rivets with the wall thickness of 1.0 mm, 1.5 mm, and 2.0 mm were employed to conduct the rivet-reinforcing experiments on the clinched joints. Mechanical interlock structure measurements and mechanical properties tests were performed on the above-mentioned reinforced joints. The results show that the rivet-reinforcing technology can significantly increase the tensile strength and improve the mechanical behavior of the clinched joint. Compared with the NRJ joint (the reinforced joint with no rivet), the static tensile strength of TRJ-1.0 (the rivet-reinforced joint with the tubular rivet of 1 mm wall thickness), TRJ-1.5 (the rivet-reinforced joint with the tubular rivet of 1.5 mm wall thickness), TRJ-2.0 (the rivet-reinforced joint with the tubular rivet of 2 mm wall thickness), and SRJ joint (the rivet-reinforced joint with the solid rivet) is separately increased by 30.05%, 24.59%, 16.28%, and 7.19%. The TRJ-1.0 joint has the highest tensile strength (1489.57 N) among the five types of reinforced joints in the cross-lap-tensile test. The energy absorption capacity of the rivet-reinforced joints decreases as the wall thickness of the tubular rivet increases. Therefore, the TRJ-1.0 joint has the highest energy absorption that is 5.890 J, while the energy absorption of the SRJ joint is the lowest, which is 2.868 J. The TRJ-1.0 joint has the most excellent strength performance in the lightweight evaluation, which with a lightweight evaluation value of [Formula: see text]. However, the TRJ-1.5 joint has the most outstanding energy absorption performance in the aspect of lightweight evaluation, with a lightweight evaluation value of [Formula: see text]. The experiment has proven that the clinched joints reinforced with 1 mm wall thickness tubular rivets have the best mechanical properties.

scholarly journals Static Mechanical Properties of Expanded Polypropylene Crushable Foam

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 249
Author(s):  
Przemysław Rumianek ◽  
Tomasz Dobosz ◽  
Radosław Nowak ◽  
Piotr Dziewit ◽  
Andrzej Aromiński
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Strain Rate ◽  
Energy Absorption ◽  
Experimental Tests ◽  
Absorption Capacity ◽  
Strain Rates ◽  
Foam Density ◽  
Energy Absorption Capacity ◽  
Closed Cell

Closed-cell expanded polypropylene (EPP) foam is commonly used in car bumpers for the purpose of absorbing energy impacts. Characterization of the foam’s mechanical properties at varying strain rates is essential for selecting the proper material used as a protective structure in dynamic loading application. The aim of the study was to investigate the influence of loading strain rate, material density, and microstructure on compressive strength and energy absorption capacity for closed-cell polymeric foams. We performed quasi-static compressive strength tests with strain rates in the range of 0.2 to 25 mm/s, using a hydraulically controlled material testing system (MTS) for different foam densities in the range 20 g/dm3 to 220 g/dm3. The above tests were carried out as numerical simulation using ABAQUS software. The verification of the properties was carried out on the basis of experimental tests and simulations performed using the finite element method. The method of modelling the structure of the tested sample has an impact on the stress values. Experimental tests were performed for various loads and at various initial temperatures of the tested sample. We found that increasing both the strain rate of loading and foam density raised the compressive strength and energy absorption capacity. Increasing the ambient and tested sample temperature caused a decrease in compressive strength and energy absorption capacity. For the same foam density, differences in foam microstructures were causing differences in strength and energy absorption capacity when testing at the same loading strain rate. To sum up, tuning the microstructure of foams could be used to acquire desired global materials properties. Precise material description extends the possibility of using EPP foams in various applications.

Experimental Analysis of Aluminum Alloy Section Bars and their Mortise and Tenon Joints under Bending Load

2011 ◽  
Vol 415-417 ◽  
pp. 2338-2344
Author(s):  
Xin Shen Huang ◽  
Qun Gao ◽  
Zhi Jian Zong
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Energy Absorption ◽  
Experimental Analysis ◽  
Absorption Capacity ◽  
Main Section ◽  
Bending Properties ◽  
Energy Absorption Capacity ◽  
Bending Load ◽  
Mortise And Tenon

Different laid modes of aluminum alloy section bars and their mortise and tenon joints were bending tested, and their mechanical properties were compared, in order to research on the influence that forming a mortise and tenon joint brought to the original bars. Opening a hole laterally and inserting another shorter bar in the hole changed the bending properties and energy absorption capacity of the original bar. In horizontal laid mode, the mortise and tenon joint was weaker than the original bar when bearing bending load, but it was stronger in vertical laid mode. Weld beads of the mortise and tenon joints were strong enough to maintain the structure integrality before the main section bars were destroyed by load.

Composite Core Cross Tube Crushing Analysis

2020 ◽  
Author(s):  
Sean Jenson ◽  
Muhammad Ali ◽  
Khairul Alam
Keyword(s):  
Energy Absorption ◽  
Compressive Loading ◽  
Deformation Mode ◽  
High Energy ◽  
Absorption Capacity ◽  
Functionally Graded ◽  
Layer By Layer ◽  
Thin Walled ◽  
The Cross ◽  
Energy Absorbing

Abstract Thin walled axial members are typically used in automobiles’ side and front chassis to improve crashworthiness of vehicles. Extensive work has been done in exploring energy absorbing characteristics of thin walled structural members under axial compressive loading. The present study is a continuation of the work presented earlier on evaluating the effects of inclusion of functionally graded cellular structures in thin walled members under axial compressive loading. A compact functionally graded composite cellular core was introduced inside a cross tube with side length and wall thickness of 25.4 mm and 3.048 mm, respectively. The parameters governing the energy absorbing characteristics such as deformation or collapsing modes, crushing/ reactive force, plateau stress level, and energy curves, were evaluated. The results showed that the inclusion of composite graded cellular structure increased the energy absorption capacity of the cross tube significantly. The composite graded structure underwent progressive stepwise, layer by layer, crushing mode and provided lateral stability to the cross tube thus delaying local tube wall collapse and promoting large localized folds on the tube’s periphery as compared to highly localized and compact deformation modes that were observed in the empty cross tube under axial compressive loading. The variation in deformation mode resulted in enhanced stiffness of the composite structure, and therefore, high energy absorption by the structure. This aspect has a potential to be exploited to improve the crashworthiness of automobile structures.

Influence of Fibre Treatment and Matrix Modification on Mechanical Properties of Flax Fibre Reinforced Mortars after Freeze/Thaw Cycles

2022 ◽  
Author(s):  
Bojan Poletanovic ◽  
Katalin Kopecsko ◽  
Ildikó Merta
Keyword(s):  
Mechanical Properties ◽  
Energy Absorption ◽  
Linseed Oil ◽  
Absorption Capacity ◽  
Flax Fibre ◽  
Energy Absorption Capacity ◽  
Freeze Thaw ◽  
Flax Fibres ◽  
Matrix Modification ◽  
Compressive And Flexural Strengths

The aim of this study was to examine the influence of flax fibre protection with the linseed oil and a matrix modification with cement substitution with metakaolin (in 10wt% and 15wt%) on the mechanical properties of cement-based mortars under severe environmental conditions of freeze/thaw cycles. Cement-based mortars (with the dimension of 40x40x160 mm3) were reinforced by 10mm long discrete flax fibres (Linumusitatissimum) and exposed to 51 freeze/thaw cycles under laboratory condition. Their compressive and flexural strengths, as well as specific energy absorption capacity were measured after freeze/thaw cycles and compared to the results of mortars cured for same time in water. Under freeze/thaw cycles mortars reinforced with linseed oil-treated fibres showed the same range of degradation of the compressive and flexural strengths, however, a more pronounced degradation of energy absorption capacity compared to non-treated fibre reinforced mortars was observed. The matrix modification, by partial cement substitution with metakaolin showed optimistic results under freeze/thaw cycles. The compressive strength when cement was partially substituted with metakaolin (in both dosages) increased whereas the flexural strength was slightly lower in case of 10wt% substitution and markedly lower under higher (15wt%) cement substitution. The most relevant is that the decrease of the energy absorption capacity of the fibre reinforced mortar was completely prevented when cement was substituted with metakaolin. It is shown that the energy absorption of the non-treated fibre reinforced mortars increases by 27% when cement was substituted with metakaolin (both 10wt% and 15wt%).

scholarly journals Tensile Behavior Characteristics of High-Performance Slurry-Infiltrated Fiber-Reinforced Cementitious Composite with Respect to Fiber Volume Fraction

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3335 ◽  
Author(s):  
Seungwon Kim ◽  
Dong Joo Kim ◽  
Sung-Wook Kim ◽  
Cheolwoo Park
Keyword(s):  
Tensile Strength ◽  
Energy Absorption ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Absorption Capacity ◽  
Fiber Reinforced ◽  
Fiber Volume ◽  
Energy Absorption Capacity ◽  
Direct Tensile ◽  
Direct Tensile Strength

Concrete has high compressive strength, but low tensile strength, bending strength, toughness, low resistance to cracking, and brittle fracture characteristics. To overcome these problems, fiber-reinforced concrete, in which the strength of concrete is improved by inserting fibers, is being used. Recently, high-performance fiber-reinforced cementitious composites (HPFRCCs) have been extensively researched. The disadvantages of conventional concrete such as low tensile stress, strain capacity, and energy absorption capacity, have been overcome using HPFRCCs, but they have a weakness in that the fiber reinforcement has only 2% fiber volume fraction. In this study, slurry infiltrated fiber reinforced cementitious composites (SIFRCCs), which can maximize the fiber volume fraction (up to 8%), was developed, and an experimental study on the tensile behavior of SIFRCCs with varying fiber volume fractions (4%, 5%, and 6%) was carried out through direct tensile tests. The results showed that the specimen with high fiber volume fraction exhibited high direct tensile strength and improved brittleness. As per the results, the direct tensile strength is approximately 15.5 MPa, and the energy absorption capacity was excellent. Furthermore, the bridging effect of steel fibers induced strain hardening behavior and multiple cracks, which increased the direct tensile strength and energy absorption capacity.

Tensile Strength of Forged Ti-6Al-4V Welded Joints by Electronic Beam Welding

2011 ◽  
Vol 255-260 ◽  
pp. 132-136
Author(s):  
Hong Yu Qi ◽  
Jian Xie ◽  
Dong Pan ◽  
Shao Lin Li ◽  
Xiao Guang Yang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Base Metal ◽  
Welded Joints ◽  
Empirical Relationship ◽  
Weld Zone ◽  
Structure Design ◽  
Microstructure And Mechanical Properties ◽  
Welded Structure ◽  
Static Tensile

Forged Ti-6Al-4V welded structure by electronic beam welding (EBW) as integrally bladed disk (blisk) structure in advanced aero-engine has been widely applied. It is necessary to analyze microstructure and mechanical properties of Ti-6Al-4V welded joints by EBW for failure analysis and structure design of blisk. Firstly the microstructure and mechanical properties of forged Ti-6Al-4V welded joints was focused on. Grains in the weld zone become coarse and large gradient organization structure appears in the heat affected zone (HAZ), which presents significant local heterogeneity. Microhardness of the weld zone is about 20% higher than that of the base metal. The size of different region of the welded joints was estimated. Then static tensile test of three different specimens were carried on. Experiment results show that the tensile and yield strength of welded joints are not less than that of the base metal. Finally the empirical relationship between strength and hardness of Ti-6Al-4V alloy is established. Tensile strength of the weld zone and the base metal were estimated. Compared to experiment data, the deviation is 3.56%, 0.097% respectively.

Effects of Foam Density and Wall Thickness Interactions on the Energy Absorption Performances

2013 ◽  
Vol 393 ◽  
pp. 393-396 ◽  
Author(s):  
Al Emran Ismail
Keyword(s):  
Energy Absorption ◽  
Wall Thickness ◽  
Foam Density ◽  
Polymeric Foam ◽  
Absorption Performance ◽  
Foam Filled

This paper discussed the effect of foam densities and wall thickness interactions on the energy absorption performances. The studies of energy absorption capabilities are important in order to reduce injuries during vehicular collisions. In this work, three different wall thicknesses are used and different polymeric foam densities are inserted into the empty tubes. The empty and foam-filled tubes are then quasi-statically compressed and forces versus displacement curves are obtained where the area under the curves represented the energy absorption performances. In order to study the interactions between foams and wall, the crushed tubes are sectioned axially and observed. It is found that when the wall thickness was less than 2.0mm, foam densities played an important role in increasing the energy absorption capabilities. However, when the wall thickness was greater than 3.0mm, lack of influence of foam densities on the energy absorption performance was observed.

Evaluation on the Sound Absorption and Mechanical Property of the Multi-Layer Needle-Punching Nonwoven

2010 ◽  
Vol 123-125 ◽  
pp. 475-478 ◽  
Author(s):  
Kou Cheng Tai ◽  
Pai Chen ◽  
Ching Wen Lin ◽  
Ching Wen Lou ◽  
Hsiu Mei Tan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Tensile Strength ◽  
Sound Absorption ◽  
Single Layer ◽  
Distinct Difference ◽  
Thermal Bonding ◽  
Needle Punching ◽  
Absorption Performance ◽  
Punching Process

In this research, we used the special needle punching process to improve the disadvantages of the ordinary needle punching process. First, we manufactured the single-layer needle punching nonwoven by the ordinary needle punching process and then nonwovens were laminated followed by needle punching. We carried on this manufacturing processing until the multiple needle-punching nonwoven reached the certain thickness and area weight which were both limited in the ordinary needle punching process. The combination of two manufacture techniques as multiple thermal bonding and multiple needle-punching freed the single needle-punching from the limit of the expected thickness and area density. In this research, we tested the mechanical properties and sound absorption of the multi-layer needle-punching nonwoven and multi-layer thermal bonding nonwoven. According to the results, the tensile strength is higher than the multi-layer thermal bonding nonwoven; however, there was no distinct difference between the multi-layer needle-punching nonwoven and multi-layer thermal bonding nonwoven on the sound absorption performance.

Sign in / Sign up

Export Citation Format

Share Document