Experimental and numerical investigation of metal-polymer riveted joints

Abstract This paper presents the modeling and analysis of the joints of metal inserts with polyamide 6 using the injection technique. Based on the conducted experiments, modeling and numerical calculations of joints were carried out for various joint configurations. Metal parts, made of steel grade DC 04, are mechanically locked with polyamide 6 (PA6) with rivets. The mechanical connection with rivets of both elements was achieved by filling the holes in the metal parts in the injection process. As part of the work, mechanical-clamp connections made of steel / PA6 were mechanically tested in a single-axis joint tensile test using appropriate tabs. The main goal was to study and numerically analyze the number of rivets and their location on the metal plate for the strength of the connector. An important element of the work was the modeling process of both the PA6 material behavior and the joint itself. As part of the experimental research, the rivet deformation was also observed using computer thermography with the use of an IR camera. The tests and simulation showed that for the sample, the polymer-metal connected with less than three rivets was destroyed by shear. On the other hand, when the polymer-metal junction was made of three rivets, the jamming mechanism was mainly related to damage to the polymer part. For these joints, the maximum values of the breaking force of the joint were obtained in uniaxial tensile and shear tests where three rivets were used. Similar values were obtained during the numerical calculations performed with the use of Abaqus software.

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Deformation Mechanism in Mechanically Coupled Polymer–Metal Hybrid Joints

Materials ◽

10.3390/ma13112512 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2512

Author(s):

Karol Bula ◽

Tomasz Sterzyński ◽

Maria Piasecka ◽

Leszek Różański

Keyword(s):

Shear Test ◽

Polyamide 6 ◽

Metal Plate ◽

Lap Shear ◽

Lap Shear Test ◽

Hybrid Joints ◽

Metal Joint ◽

Polymer Metal ◽

Metallic Parts ◽

Sample Damage

In this, work, metal inserts were joined with polyamide 6 by using the injection-molding technique. The metal parts, made of steel grade DC 04, were mechanically interlocked with polyamide 6 (PA6) by rivets as a mechanical connection between both components in the form of s polymer filling the holes in the metallic parts. The mechanical-interlocking joints made of steel/PA6 were mechanically tested in a tensile-lap-shear test. The damage behavior of the joined materials in relation to rivet number and position on the metal plate was studied. The observation of rivet deformation was also conducted by infrared IR thermography. The study showed that, for polymer–metal joined samples with fewer than three rivets, the destruction of rivets by shearing meant sample damage. On the other hand, when the polymer–metal joint was made with three or four rivets, the disruption mechanism was mostly related to the polymer part breaking. The maximal values of the joint’s failure force under tensile-shear tests were achieved for samples where three rivets were used. Moreover, strong correlation was found between the surface temperature of the samples and their maximal force during the tensile-lap-shear test.

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Effect of Jet-to-Jet Distance and Pipe Position on Flow and Heat Transfer Features of Active Clearance Control Systems

10.1115/gt2021-59158 ◽

2021 ◽

Author(s):

Lorenzo Cocchi ◽

Alessio Picchi ◽

Bruno Facchini ◽

Riccardo Da Soghe ◽

Lorenzo Mazzei ◽

...

Keyword(s):

Heat Transfer ◽

Target Surface ◽

Reynolds Numbers ◽

Metal Plate ◽

Target Distance ◽

Target Plate ◽

Ir Camera ◽

Supply Pipe ◽

Heating Up ◽

Clearance Control

Abstract The goal of the present work is to investigate the effect of supply pipe position on the heat transfer features of various active clearance control (ACC) geometries, characterized by different jet-to-jet distances. All geometries present 0.8 mm circular impingement holes arranged in a single row. The jets generated by such holes cool a flat target surface, which is replicated by a metal plate in the experimental setup. Measurements are performed using the steady-state technique, obtained by heating up the target plate thanks to an electrically heated Inconel foil applied on the side of the target opposite to the jets. Temperature is also measured on this side by means of an IR camera. Heat transfer is then evaluated thanks to a custom designed finite difference procedure, capable of solving the inverse conduction problem on the target plate. The effect of pipe positioning is studied in terms of pipe-to-target distance (from 3 to 11 jet diameters) and pipe orientation (i.e. rotation around its axis, from 0° to 40° with respect to target normal direction), while the investigated jet Reynolds numbers range from 6000 to 10000. The obtained results reveal that heat transfer is maximized for a given pipe-to-target distance, dependent on both jet-to-jet distance and target surface extension. Pipe rotation also affects the cooling features in a non-monotonic way, suggesting the existence of different flow regimes related to jet inclination.

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Fatigue behaviour of material-adapted fibre-reinforced polymer/metal joints

Technologies for Lightweight Structures (TLS) ◽

10.21935/tls.v3i1.122 ◽

2021 ◽

Vol 3 (1) ◽

pp. 81-88

Author(s):

Colin Gerstenberger ◽

Tomasz Osiecki ◽

Lothar Kroll

Keyword(s):

Polyamide 6 ◽

Fatigue Behaviour ◽

High Yield ◽

Cold Forming ◽

Shear Loads ◽

Polymer Metal ◽

Lightweight Engineering ◽

Micro Alloyed Steel ◽

Reinforced Thermoplastics ◽

Cross Tension

By regarding the needs and requirements in modern multi-material joining, the Flow Drill Joining Concept (FDJ) was developed at the Chemnitz University of Technology. The technology allows an efficient and material-adapted joining of thin metal sheets with continuous fibre-reinforced thermoplastics, as required in modern lightweight engineering. For a better understanding of their fatigue behaviour, single-lap FDJ joints were examined in quasi-static and dynamic tests regarding shear loads, cross tension and superimposed shear/cross tension loads. By way of example, joints between micro-alloyed steel with high yield strength for cold forming and a continuous glass/carbon fibre-reinforced polyamide 6 were investigated. The fatigue curves show inclinations between k = 8.01 (shear loads) and k = 5.17 (cross tension loads), depending on the applied load angle. The results of the fatigue testings represent a basis for the enhancement of a failure criterion for FRP/metal joints in highly stressed multi-material designs.

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Modeling and analysis of a taper ionic polymer metal composite energy harvester

ISSS Journal of Micro and Smart Systems ◽

10.1007/s41683-020-00060-3 ◽

2020 ◽

Vol 9 (2) ◽

pp. 143-150

Author(s):

Satya Narayan Patel ◽

Sujoy Mukherjee

Keyword(s):

Energy Harvester ◽

Metal Composite ◽

Ionic Polymer Metal Composite ◽

Modeling And Analysis ◽

Ionic Polymer ◽

Polymer Metal ◽

Composite Energy

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Inverse Mechanical Characterization of Tissue Engineered Heart Valves

ASME 2008 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2008-192521 ◽

2008 ◽

Author(s):

Martijn A. J. Cox ◽

Jeroen Kortsmit ◽

Niels J. B. Driessen ◽

Carlijn V. C. Bouten ◽

Frank P. T. Baaijens

Keyword(s):

Heart Valves ◽

Soft Tissues ◽

Mechanical Characterization ◽

Tensile Tests ◽

Material Behavior ◽

Uniaxial Tensile ◽

Mechanical Conditioning ◽

Indentation Tests ◽

Tissue Engineered Heart Valves

Over the last few years, research interest in tissue engineering as an alternative for current treatment and replacement strategies for cardiovascular and heart valve diseases has significantly increased. In vitro mechanical conditioning is an essential tool for engineering strong implantable tissues [1]. Detailed knowledge of the mechanical properties of the native tissue as well as the properties of the developing engineered constructs is vital for a better understanding and control of the mechanical conditioning process. The nonlinear and anisotropic behavior of soft tissues puts high demands on their mechanical characterization. Current standards in mechanical testing of soft tissues include (multiaxial) tensile testing and indentation tests. Uniaxial tensile tests do not provide sufficient information for characterizing the full anisotropic material behavior, while biaxial tensile tests are difficult to perform, and boundary effects limit the test region to a small central portion of the tissue. In addition, characterization of the local tissue properties from a tensile test is non-trivial. Indentation tests may be used to overcome some of these limitations. Indentation tests are easy to perform and when indenter size is small relative to the tissue dimensions, local characterization is possible. We have demonstrated that by recording deformation gradients and indentation force during a spherical indentation test the anisotropic mechanical behavior of engineered cardiovascular constructs can be characterized [2]. In the current study this combined numerical-experimental approach is used on Tissue Engineered Heart Valves (TEHV).

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Nonlinear Structural Dynamics of Macro-Fiber Composite Cantilevers for Resonant Actuation

Volume 2: Modeling, Simulation and Control of Adaptive Systems; Integrated System Design and Implementation; Structural Health Monitoring ◽

10.1115/smasis2017-3927 ◽

2017 ◽

Cited By ~ 1

Author(s):

David Tan ◽

Paul Yavarow ◽

Alper Erturk

Keyword(s):

Linear Models ◽

Piezoelectric Materials ◽

Fiber Composite ◽

Material Behavior ◽

Mathematical Framework ◽

Experimental Frequency ◽

Modeling And Analysis ◽

Dissipative Effects ◽

Macro Fiber Composite ◽

Electric Effect

Macro-fiber composite (MFC) piezoelectric materials are used in a variety of applications employing the converse piezo-electric effect, ranging from bioinspired actuation to vibration control. Most of the existing literature to date considered linear material behavior for geometrically linear oscillations. However, in many applications, such as bioinspired locomotion using MFCs, material and geometric nonlinearities are pronounced and linear models fail to represent and predict the governing dynamics. The predominant types of nonlinearities manifested in resonant actuation of MFC cantilevers are piezoelectric softening, geometric hardening, inertial softening, as well as internal and external dissipative effects. In the present work, we explore nonlinear actuation of MFC cantilevers and develop a mathematical framework for modeling and analysis. An in vacuo actuation scenario is considered for a broad range of voltage actuation levels to accurately identify the sources of dissipation. Several experiments are conducted for an MFC bimorph cantilever, and model simulations are compared with nonlinear experimental frequency response functions under resonant actuation. The resulting experimentally validated framework can be used for simulating the dynamics of MFCs under resonant actuation, as well as parameter identification and structural optimization for nonlinear operation regime.

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Modeling and Analysis of Elastoplastic Impacts on Supported Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.471-472.367 ◽

2011 ◽

Vol 471-472 ◽

pp. 367-372 ◽

Cited By ~ 3

Author(s):

Majed A. Majeed ◽

Ahmet S. Yigit ◽

Andreas P. Christoforou

Keyword(s):

Isotropic Material ◽

Composite Layer ◽

Transversely Isotropic ◽

Material Behavior ◽

Model Parameters ◽

Fe Model ◽

Transversely Isotropic Material ◽

Spherical Object ◽

Modeling And Analysis ◽

Plastic Indentation

This paper presents an elastoplastic impact model for a spherical object impacting a supported composite layer or a half-space. The model utilizes a contact law that has been developed based on elastic-plastic and fully plastic indentation theories. For an impact event, the model parameters can easily be obtained analytically, computationally using Finite Elements (FE), and from experiments, by assuming transversely isotropic material behavior. Simulations are compared to those from a nonlinear FE model developed in ABAQUS, and to limited experimental data, with excellent results.

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Evolution of Roughness on Straining of Interstitial Free – IF Steel Sheet

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.504-506.83 ◽

2012 ◽

Vol 504-506 ◽

pp. 83-88 ◽

Cited By ~ 2

Author(s):

Ricardo Kirchhof Unfer ◽

José Divo Bressan

Keyword(s):

Plastic Strain ◽

Tensile Test ◽

Steel Sheet ◽

Material Behavior ◽

Uniaxial Tensile ◽

Interstitial Free ◽

If Steel ◽

Local Necking ◽

Incremental Step ◽

If Steel Sheet

This study aims to assess the evolution of surface roughness and waviness parameters with plastic strain in Interstitial Free – IF steel sheet. For the achievement of this study, it was considered various roughness and waviness profile parameters such as: arithmetic average roughness (Ra), maximum distance peak-valley (Rt), average waviness (Wa) and waviness of the total height peak-valley (Wt). Tensile test specimens of IF steel at 0º, 45º and 90º to the direction of rolling were fabricated. After preparing the sheet proof specimens, it was performed simple tensile tests and measurements of roughness and waviness of the specimen surface at various strain stages resulting in a large quantity of data. During the tensile test, it has been measured the following plastic strain to indicate the incremental step: (e1) longitudinal strain and (e2) transverse strain. From these data, it was possible to obtain points needed to plot the curves of roughness and waviness parameters versus strain and to determine the material behavior using equations of the equivalent strain. From the curves drawn it was possible to see how the material roughness and waviness behaves during the straining in the uniaxial tensile state, with the possibility to predict the influence of plastic strain on roughness and waviness parameters and the onset of local necking of IF steel sheet. The waviness parameters Wt is the best for characterizing the onset of local necking.

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Finite Element Analysis on Nitinol Medical Applications

Advances in Bioengineering ◽

10.1115/imece2002-32601 ◽

2002 ◽

Cited By ~ 7

Author(s):

Xiao-Yan Gong ◽

Alan R. Pelton

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Material Behavior ◽

Nonlinear Material ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Element Analysis ◽

Highly Nonlinear ◽

Device Applications ◽

Specific Material

Nitinol, an alloy of about 50% Ni and 50% Ti, is a very unique material. At constant temperature above its Austenite finish (Af) temperature, under uniaxial tensile test, the material is highly nonlinear and capable of large deformation to the ultimate strain on the order of 15%. This material behavior, known as superelasticity, along with its excellent biocompatibility and corrosion resistance, makes Nitinol a perfect material candidate for many medical device applications. However, the nonlinear material response also requires a specific material description to perform the stress analysis. The user developed material subroutine from HKS/West makes the simulation of the Nitinol devices possible. This article presents two case studies of the nonlinear finite element analysis using ABAQUS/Standard and the Nitinol UMAT.

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