Static Strength Analysis and Experimental Research of Clinched Joints By Two-strokes Flattening Clinching Method

Abstract Clinching technology is widely used to join sheet materials in manufacturing fields, especially in automotive lightweight applications. However, the clinched joints have a weak static strength and high protuberance, which influence the application of the clinching technology. In order to improve the static strength and decrease the protuberance height of clinched joint, a new method to join aluminum alloy sheet materials with two-strokes flattening clinching (TFC) was investigated in this paper. The tension-shear strength, cross-tension strength, energy absorption and failure modes of clinched joint and TFC joint were investigated. Furthermore, the stiffness and the hardening exponent of the joints under different experimental tests were studied. The results indicated that the mechanical behaviors of the joints were optimal when the forming force was 35 kN. The maximum cross-tension and tension-shear strength of TFC joint were increased by 514 N and 1145 N on average compared with the initial clinched joint. The main failure modes of the joints were the neck fracture mode under the tension-shearing and cross-tension test. In addition, the stiffness and hardening exponent explained the variation of the mechanical properties of the joints under different forming forces.

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A Performance Study of Self-Piercing Riveting of Aluminum and Copper Alloy Sheets

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.734-737.2460 ◽

2013 ◽

Vol 734-737 ◽

pp. 2460-2464 ◽

Cited By ~ 1

Author(s):

Cheng Jiang Deng ◽

Xiao Cong He ◽

Bao Ying Xing

Keyword(s):

Copper Alloy ◽

Experimental Tests ◽

Type Specimen ◽

Static Strength ◽

Alloy Sheet ◽

Performance Study ◽

Type Specimens ◽

Lap Shear ◽

Shear Type ◽

Force Displacement

This paper studied the performance of self-piercing riveting (SPR) of aluminum and copper alloy sheet. The SPR process of two copper alloy sheets was analyzed by experimental tests and finite elements stimulation, and good agreements between the simulations and test results of SPR process were obtained. Two different specimen geometries were adopted in experiment: a lap-shear type specimen and a T type specimen. The influence of combination of different materials on the static strength of SPR joints were studied through the tensile-shear and peeling experiments, and the strength of the SPR joints were evaluated by the force-displacement curves of two type specimens. The failure mechanisms corresponding to the static strength were also discussed. On the other hand, the engineering stress - strain curves of two materials have also been studied roughly. These results could provide designer engineers with some application messages of SPR.

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A New Method for Analyzing X-Cor Sandwich’s Shear Strength

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.510.356 ◽

2012 ◽

Vol 510 ◽

pp. 356-361

Author(s):

Xu Dan Dang ◽

Shao Jie Shi ◽

Yi Guo ◽

Jun Xiao

Keyword(s):

Finite Element ◽

Shear Strength ◽

Failure Criterion ◽

Failure Modes ◽

Failure Process ◽

Stiffness Degradation ◽

Strength Analysis ◽

Finite Element Software ◽

Pull Out ◽

Comparison Results

The finite element software was used to get the X-cor sandwich’s shear strength. During the shear strength analysis, the failure criterion and materials stiffness degradation rules fitting for the analysis of X-cor sandwich’s failure mechanism were proposed and the X-cor sandwich’s failure process and modes were also clarified. According to the failure criterion we used the elements with stiffness degradation and their distributions in the finite element model to simulate the types and propagation path of the failure and the failure mechanisms of X-cor sandwich under shear were explained. The finite element analysis indicates during the shear firstly the resin regions fail and then the multiple failure modes of Z-pin pull-out from the face-sheet, Z-pin shear off and Z-pin buckling all exist. The propagation paths of the failure elements are dispersive. By contrasting the finite element results and test results the values are consistent well and the error range is -10.4%~7.4%. The comparison results show that the failure criterion and stiffness degradation rules are reasonable and this method can be used to predict the X-cor sandwich’s shear strength.

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Lightweight design and static strength analysis of battery box for electric vehicle

Proceedings of the 2019 International Conference on Robotics, Intelligent Control and Artificial Intelligence - RICAI 2019 ◽

10.1145/3366194.3366244 ◽

2019 ◽

Author(s):

Lingli Chen ◽

Xiaoyu Zhao

Keyword(s):

Electric Vehicle ◽

Lightweight Design ◽

Static Strength ◽

Strength Analysis

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Microstructure and Mechanical Performance of Resistance Spot Welded Martensitic Advanced High Strength Steel

Processes ◽

10.3390/pr9061021 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1021

Author(s):

Yunzhao Li ◽

Huaping Tang ◽

Ruilin Lai

Keyword(s):

Mechanical Properties ◽

Failure Modes ◽

Mechanical Performance ◽

Strong Dependence ◽

High Strength ◽

Weld Nugget ◽

Resistance Spot ◽

Pull Out ◽

Cross Tension ◽

Spot Welded

Resistance spot welded 1.2 mm (t)-thick 1400 MPa martensitic steel (MS1400) samples are fabricated and their microstructure, mechanical properties are investigated thoroughly. The mechanical performance and failure modes exhibit a strong dependence on weld-nugget size. The pull-out failure mode for MS1400 steel resistance spot welds does not follow the conventional weld-nugget size recommendation criteria of 4t0.5. Significant softening was observed due to dual phase microstructure of ferrite and martensite in the inter-critical heat affected zone (HAZ) and tempered martensite (TM) structure in sub-critical HAZ. However, the upper-critical HAZ exhibits obvious higher hardness than the nugget zone (NZ). In addition, the mechanical properties show that the cross-tension strength (CTS) is about one quarter of the tension-shear strength (TSS) of MS1400 weld joints, whilst the absorbed energy of cross-tension and tension-shear are almost identical.

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Additively Manufactured Parts Made of a Polymer Material Used for the Experimental Verification of a Component of a High-Speed Machine with an Optimised Geometry—Preliminary Research

Polymers ◽

10.3390/polym13010137 ◽

2020 ◽

Vol 13 (1) ◽

pp. 137

Author(s):

Artur Andrearczyk ◽

Bartlomiej Konieczny ◽

Jerzy Sokołowski

Keyword(s):

Polymer Material ◽

High Speed ◽

Numerical Models ◽

Flow Analysis ◽

Experimental Tests ◽

Strength Analysis ◽

Compressor Wheel ◽

Operational Characteristics ◽

3D Printed ◽

Novel Method

This paper describes a novel method for the experimental validation of numerically optimised turbomachinery components. In the field of additive manufacturing, numerical models still need to be improved, especially with the experimental data. The paper presents the operational characteristics of a compressor wheel, measured during experimental research. The validation process included conducting a computational flow analysis and experimental tests of two compressor wheels: The aluminium wheel and the 3D printed wheel (made of a polymer material). The chosen manufacturing technology and the results obtained made it possible to determine the speed range in which the operation of the tested machine is stable. In addition, dynamic destructive tests were performed on the polymer disc and their results were compared with the results of the strength analysis. The tests were carried out at high rotational speeds (up to 120,000 rpm). The results of the research described above have proven the utility of this technology in the research and development of high-speed turbomachines operating at speeds up to 90,000 rpm. The research results obtained show that the technology used is suitable for multi-variant optimization of the tested machine part. This work has also contributed to the further development of numerical models.

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Report no. 490, the weathering of aluminum alloy sheet materials used in aircraft

Journal of the Franklin Institute ◽

10.1016/s0016-0032(34)90747-x ◽

1934 ◽

Vol 218 (5) ◽

pp. 639

Keyword(s):

Aluminum Alloy ◽

Alloy Sheet ◽

Aluminum Alloy Sheet ◽

Sheet Materials ◽

Materials Used

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Ramie fiber reinforced composites with flame retardant structure design: flammability, smoke suppression, and mechanical properties

Journal of Polymer Engineering ◽

10.1515/polyeng-2021-0221 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Chenkai Zhu ◽

Lei Nie ◽

Xiaofei Yan ◽

Jiawei Li ◽

Dongming Qi

Keyword(s):

Shear Strength ◽

Iron Oxide ◽

Heat Release ◽

Flame Retardant ◽

Interlaminar Shear Strength ◽

Smoke Suppression ◽

Strength Analysis ◽

Ramie Fiber ◽

Composite Surface ◽

Interlaminar Shear

Abstract In this work, the structure of composite was designed as Core Stack and Surface Stack, which was treated with the expandable graphite (EG) and metal oxides such as iron oxide (IO), hydroxyapatite (HA), and aluminum tri-hydroxide (ATH). The mechanical performance of composites was characterized via flexural performance and interlaminar shear strength analysis. The flame retardance and smoke suppression of composite was explored in detail by LOI, UL-94, and cone calorimeter test. The findings presented that flexural properties of composites were observed to decrease due to delamination of surface stack, whilst no significant effect on interlaminar shear strength. In comparison with control composite, the loading of metal oxide into composite Surface Stack led to the reduction of peak heat release rate, total heat release, and fire growth index effectively. Moreover, the remarkable decrease in total smoke production could be observed due to the addition of iron oxide and the flame retardant mechanism was discussed. This study was the preliminary exploration of composite with flame retardant design which could be potential solution to improve flame retardancy and smoke suppression of composite with better mechanical structure preservation.

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Influence of coarse aggregate on shear resistance of self-consolidating concrete beams

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952017000100003 ◽

2017 ◽

Vol 10 (1) ◽

pp. 30-40

Author(s):

G. SAVARIS ◽

R. C. A. PINTO

Keyword(s):

Shear Strength ◽

Failure Modes ◽

Coarse Aggregate ◽

Concrete Beams ◽

Shear Resistance ◽

Self Consolidating Concrete ◽

Coarse Aggregates ◽

Lower Shear ◽

Nominal Size ◽

High Flowability

Abstract Self-consolidating concrete is characterized by its high flowability, which can be achieved with the addition of superplasticizer and the reduction of the amount and size of coarse aggregates in the concrete mix. This high flowability allows the concrete to properly fill the formwork without any mechanical vibration. The reduction in volume and particle size of the coarse aggregates may result in lower shear strength of beams due to a reduced aggregate interlock. Therefore, an experimental investigation was conducted to evaluate the influence of the reduction in the volume fraction and the nominal size of coarse aggregate on concrete shear strength of self-consolidating beams. Six concrete mixes were produced, four self-consolidating and two conventionally vibrated. A total of 18 beams, with flexural reinforcement but without shear reinforcement were cast. These beams were tested under a four-point loading condition. Their failure modes, cracking patterns and shear resistances were evaluated. The obtained shear resistances were compared to the theoretical values given by the ACI-318 and EC-2 codes. The results demonstrated a lower shear resistance of self-consolidating concrete beams, caused mainly due to the reduced aggregate size.

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Fatigue Failure Modes in Self-Piercing Riveted Aluminium Alloy Joints

Volume 3 ◽

10.1115/esda2004-58320 ◽

2004 ◽

Author(s):

L. Han ◽

K. Young ◽

R. Hewitt ◽

A. Chrysanthou ◽

J. M. O’Sullivan

Keyword(s):

Aluminium Alloy ◽

Fatigue Failure ◽

Failure Modes ◽

Surface Condition ◽

Fatigue Behaviour ◽

Alloy Sheet ◽

Static Tests ◽

Failure Patterns ◽

Interfacial Conditions ◽

Sheet Surface

Self-piercing riveting, as an alternative joining method to spot-welding, has attracted considerable interest from the automotive industry and has been widely used in aluminium intensive vehicles. One of the important factors that need to be considered is the effect of cyclic loading in service, leading to possible fatigue failure. The previous work reported in the public domain on the behaviour of self-piercing rivets has mainly focused on static tests. The work which is reported in this paper is concerned with the fatigue behaviour of single-rivet joints, joining two 2mm 5754 aluminium alloy sheets. The investigation also examined the effect of interfacial conditions on the fatigue behaviour. A number of fatigue failure mechanisms were observed based on rivet fracture, sheet fracture and combinations of these. The investigation has shown that they were dependent on the applied load and the sheet surface condition. Three-parameter Weibull analysis, using Reliasoft Weibull ++5.0 software, was conducted to analyse the experimental results. The analysis enabled the prediction of early-type failure (infant mortality failure) and wear-out failure patterns depending on the condition of the self-piercing riveted joints and the alloy sheet surface.

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