Investigation of the mechanical performance of hybrid bolted-bonded joints subjected to different ageing conditions: Effect of geometrical parameters and bolt size

A topology optimization (TO) method is used to develop new and efficient unit cells to be used in additively manufactured porous lattice structures. Two types of unit cells including solid and thin-walled shell-type ones are introduced for generating the desired regular and functionally graded (FG) lattice structures. To evaluate structural stiffness and crushing behavior of the proposed lattice structures, their mechanical properties, and energy absorption parameters have been calculated through implementing finite element (FE) simulations on them. To validate the simulations, two samples were fabricated by a stereolithography (SLA) machine. Besides, the effects of geometrical parameters and optimizing scheme of the unit cells on the mechanical properties of the proposed structures are studied. Consequently, energy absorption parameters have been calculated and compared for both the solid and thin-walled lattice structures to evaluate their ability in energy absorption. It was found in general that for the solid lattice structures, the mechanical properties, and the crushing parameters are directly affected by porosity though in shell-type ones superior mechanical properties could be achieved even for a smaller proportion of material usage.

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Influence of Filler Amount and Content on the Mechanical Performance of Joints Bonded with Metal Powder Filled Adhesive

Materials Science Forum ◽

10.4028/www.scientific.net/msf.773-774.226 ◽

2013 ◽

Vol 773-774 ◽

pp. 226-233

Author(s):

Nergizhan Kavak ◽

Erhan Altan

Keyword(s):

Surface Roughness ◽

Mechanical Strength ◽

Shear Test ◽

Mechanical Performance ◽

Bonded Joints ◽

Aluminium Powder ◽

Lap Shear ◽

Lap Shear Test ◽

Adhesive Bonded Joints ◽

Single Lap Shear Test

The objective of this study is to investigate the surface roughness that effect the capability of adhesive with adding aluminium powder and 63/37 Sn-Pb soft solder powder to the epoxy to increase the mechanical strength of joints. The adhesive strength of the joints was determined by utilizing the single-lap shear test. As seen from the experiments, the surface roughness has an important effect on the strength of adhesive bonded joints. Experimental results show that joints prepared by adhesive which was modified, adding in the amount of 5 wt% 63/37 Sn-Pb powder have more mechanical strength than joints compared to one which is prepared by adding aluminium powder with different ratios as 5, 25,50 wt%.

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Mechanical Performance Analysis of Composite Scarf Joints with Debond Flaw

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1016.95 ◽

2014 ◽

Vol 1016 ◽

pp. 95-99 ◽

Cited By ~ 1

Author(s):

Xia Guo ◽

Zeng Shan Li ◽

Wen Chao Zhang ◽

Ri Ming Tan ◽

Zhi Dong Guan

Keyword(s):

Failure Mode ◽

Mechanical Performance ◽

Load Carrying Capacity ◽

Bonded Joints ◽

The Finite Element Method ◽

Adhesively Bonded ◽

Adhesively Bonded Joints ◽

Load Carrying ◽

Scarf Joints ◽

Bond Region

The adhesive structural mechanical performance is influenced by debond flaw. This paper presents a research on the effect of flaws on the mechanical performance of composite scarf joints. The experimental results show that the load-carrying capacity of composite scarf joints changed along with the location of the debond flaw. The location of the flaw in the bondline influences the failure mode. Additionally, the finite element method was employed to obtain the failure mode of the composite scarf joint. The adhesively bonded joints were modeled using ABAQUS software. The computational results show that flaws located at the edge of the bond region result in more pronounced load reduction than which located at the middle of bond region.

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Nondestructive Evaluation of Adhesively Bonded Joints in Graphite/Epoxy Composites Using Acousto-Ultrasonics

Journal of Pressure Vessel Technology ◽

10.1115/1.2929050 ◽

1992 ◽

Vol 114 (3) ◽

pp. 344-352 ◽

Cited By ~ 5

Author(s):

S. Tanary ◽

Y. M. Haddad ◽

A. Fahr ◽

S. Lee

Keyword(s):

Mechanical Performance ◽

Bonded Joints ◽

Propagation Characteristics ◽

Lap Joint ◽

Adhesively Bonded ◽

Shear Tests ◽

Adhesively Bonded Joints ◽

Testing Conditions ◽

Single Lap Joint ◽

Film Adhesive

This paper is concerned with the use of the acousto-ultrasonic technique to evaluate nondestructively the mechanical performance of composite bonded joints. In this context, acousto-ultrasonic measurements followed by destructive shear tests were performed on single lap joint specimens made from graphite/epoxy adherends joined with FM 300 film adhesive. The results indicate a good correlation between acousto-ultransonic wave propagation characteristics and the shear strength of the bonded joints under different testing conditions. These correlations suggest that an estimation of the joint strength can be made by using acousto-ultrasonics provided that the measurement system is calibrated for variations of the material and geometry of the specimen.

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A computational study on the effect of bending number on superelastic behavior of NiTi for medical application

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x20942568 ◽

2020 ◽

Vol 31 (18) ◽

pp. 2117-2127

Author(s):

Fardin Nematzadeh

Keyword(s):

Free Energy ◽

Aortic Aneurysm ◽

Thoracic Aortic Aneurysm ◽

Mechanical Performance ◽

Numerical Study ◽

Computational Study ◽

Radial Strain ◽

Segment Length ◽

Geometrical Parameters ◽

Superelastic Behavior

NiTi self-expanding stents can be exploited in medical applications such as thoracic aortic aneurysm owing to its effects on minimizing problems such as low twistability, unsuitable dynamic performance, and inadequate radial mechanical strength. The present simulation models NiTi superelasticity based on the thermodynamics of the Helmholtz free energy (Auricchio theory) and the thermodynamics of the Gibbs free energy (Lagoudas theory). The three-dimensional nonlinear finite element method is used to evaluate the influences of bend number on the superelastic manners of new geometries designed for Z-shaped thoracic aortic aneurysm NiTi stents by the use of a radial strain (crimping) test. NiTi stents with the lowest number of bends and highest segment length showed the best mechanical performance owing to their lower chronic outward force, higher radial resistive force, and whole superelastic behavior. This numerical study can provide a suitable way of assessing the biomechanical properties of thoracic aortic aneurysm stents given the effects of geometrical parameters.

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Dimensioning of the bonded lap joint

Research in Agricultural Engineering ◽

10.17221/35/2009-rae ◽

2010 ◽

Vol 56 (No. 2) ◽

pp. 59-68 ◽

Cited By ~ 16

Author(s):

M. Müller ◽

D. Herák

Keyword(s):

Laboratory Experiments ◽

Lap Joints ◽

Production Costs ◽

Geometrical Parameters ◽

Loading Capacity ◽

Deformation Characteristics ◽

Bonded Joints ◽

Lap Joint ◽

Joint Geometry ◽

Bonded Joint

Bonded joint is a complex assembly, which creation and following use is limited by a range of factors. The primary factors are the properties of the bonded material and of the adhesive. The stress distribution in the bonded joint is substantially influenced by the bonded joint geometry and by the deformation characteristics. Laboratory experiments are intent on the above mentioned influences for bonded lap joints, which are very used in practice. The geometrical parameters of bonded joints are substantial for the constructional parameters and for costs determination. At the lower lapping length the failure of the bonded joint occurs and the maximum loading capacity of the bonded material is not fully utilized. On the contrary when using the lapping length over its optimum value the failure of the bonded material occurs. At the same time the total weight of the bonded assembly increases. Therefore it is important to determine the bonded joint optimum values which secure the reliability and which do not increase the production costs.  

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