Investigation on Ultrasonic Welding Attributes of Novel Carbon/Elium® Composites

Joining large and complex polymer–matrix composite structures is becoming increasingly important in industries such as automobiles, aerospace, sports, wind turbines, and others. Ultrasonic welding is an ultra-fast joining process and also provides excellent joint quality as a cost-effective alternative to other joining processes. This research aims at investigating the welding characteristics of novel methyl methacrylate Elium®, a liquid thermoplastic resin. Elium® is the first of its kind of thermoplastic resin, which is curable at room temperature and is suitable for mass production processes. The welding characteristics of Elium® composites were investigated by optimizing the welding parameters with specially designed integrated energy directors (ED) and manufactured using the Resin transfer molding process. The results showed a 23% higher lap shear strength for ultrasonically welded composite joints when compared to the adhesively bonded joints. The optimized welding time for the ultrasonic welded joint was found to be 1.5 s whereas it was 10 min for the adhesively bonded joint. Fractographic analysis showed the significant plastic deformation and shear cusps formation on the fractured surface, which are typical characteristics for strong interfacial bonding.

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Impact of manufacturing imperfections and surface defects on stress–strain behaviour of flexible adhesive joints

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/0954408920927634 ◽

2020 ◽

Vol 234 (5) ◽

pp. 499-510

Author(s):

P Liška ◽

B Nečasová ◽

J Šlanhof ◽

P Schmid ◽

V Motyčka

Keyword(s):

Joint Strength ◽

Surface Defects ◽

Negative Impact ◽

Deformation Behaviour ◽

Adhesively Bonded ◽

Adhesion Promoter ◽

Premature Failure ◽

Lap Shear ◽

Manufacturing Techniques ◽

Adhesively Bonded Joint

Precise adherence to the manufacturer’s instructions and requirements plays an important role in various installation processes. The presented paper deals with the evaluation of the effect of manufacturing imperfections and surface defects on the failure behaviour of flexible adhesive intended for façade application. The failure to comply with the accepted procedures is more common in construction practice than in other sectors of the industry, mostly due to the surrounding conditions and lack of trained supervision. Unfortunately, this may lead to premature failure of adhesively bonded joints and a considerable shortening of the service life of the entire construction. To determine the potential of the risk, five types of artificially applied (a) manufacturing imperfections: (1) application on wet adhesion promoter, (2) application after the expiry of the laying-time, (3) curing of samples at +1℃ (b) surface defects: (4) application on a wet substrate and (5) application on a dirty surface, were suggested. Moreover, the Taguchi L32 orthogonal array design was used to arrange the test setup of all possible combinations. The 1 K polyurethane adhesive was applied in tensile butt joints and single-lap shear joints composed of aluminium alloy and thermally modified wood substrates. The obtained results confirmed that non-observance of the required manufacturing techniques and recommended procedures can have a negative impact on the decrease of the adhesively bonded joint strength and deformation behaviour. Surprisingly, the most critical was not the combination of all suggested types of imperfections and defects. The performed one-way ANOVA revealed that the most perilous was the combination of types 2 and 4 in the tensile test with 77% joint strength reduction. In the shear test, the most critical was the combination of all types of imperfection and defects which led also to a 77% drop of shear strength.

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Investigation On Mechanism of Ultrasonic Welding AZ31B / 5052 Joint With Laser Texturing On Mental Surface

10.21203/rs.3.rs-1151412/v1 ◽

2021 ◽

Author(s):

Cailing Wang ◽

Yanfeng Xing ◽

Jingyao Hu ◽

Junding Luo ◽

Sheng Zeng

Keyword(s):

Weld Interface ◽

Mechanical Analysis ◽

Ultrasonic Welding ◽

Weld Strength ◽

Welding Parameters ◽

Al Alloy ◽

Weld Quality ◽

Laser Texturing ◽

Grid Pattern ◽

Lap Shear

Abstract The ultrasonic welding was carried out to improve the quality of dissimilar Al/Mg alloys joint. The effects of laser texturing on the microstructure and mechanism of AZ31B/5052 joint connected by ultrasonic welding were also investigated. A series of laser texturing experiments on Al alloy (5052) and Mg alloy (AZ31B) were performed to determine the process parameters and their ef-fect on ultrasonic weld quality, especially on weld strength. Little effect was attained by opti-mizing welding parameters in improving mechanical properties. Both welding parameters and different texture pattern were investigated to obtain good weld quality. The connection mecha-nisms of joints were discussed based on the analysis of weld interface morphology, microstruc-ture evolution. Mechanical analysis of particle and movement of material atoms were analyzed in the study to explain the connect mechanism. The results show that the better lock-interface and lager lap shear strength were attained by laser texture addition and optimal welding parameters. Compared with the untextured joint, swirling bonding interface was obtained after the laser tex-ture. The laser texture with grid pattern was found to raise the strength up to 26% higher maxi-mum tensile-shear load than the joints obtained with the untextured surface.

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Experimental and Analytical Investigations of the Dynamic Analysis of Adhesively Bonded Joints for Composite Structures

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.147-149.663 ◽

2009 ◽

Vol 147-149 ◽

pp. 663-675 ◽

Cited By ~ 1

Author(s):

S.M. Ghoneam ◽

A.A. Hamada ◽

M.I. El-Elamy

Keyword(s):

Dynamic Analysis ◽

Composite Structures ◽

Damping Capacity ◽

Bonded Joints ◽

Adhesively Bonded ◽

Adhesively Bonded Joints ◽

Line Configuration ◽

Bonded Joint ◽

Adhesive Bonded Joints ◽

Adhesively Bonded Joint

Adhesively bonded joints are used extensively in various industries. Some imperfections like holes, thermal residual stresses occurring in the bolted, welded, riveted, and soldered joints don't take place in adhesively bonded joints. Hence, the main advantages of bonded joint are lightness, sealing, corrosion resistance, heat and sound isolation, damping, and quickly mounting facility which have been highly proved. This paper introduces an attempt to study the dynamic analysis of adhesively bonded joint for composite structures to investigate mainly the influences of lamina code number, bonded adhesive line configuration and boundary condition on the dynamic behavior of the test specimens containing composite assembly. The numerical based on the use of finite element model (FEM) modified by introducing unified mechanical properties are represented and applied to compute efficiently the Eigen-nature for composite bonded structures. The experimental tests are conducted to investigate such adhesive bonded joints using two different techniques. The first technique includes an ultrasonic technique in which the magnetostractive pulse echo delay-line for material characterization of composite material is used. The second technique is bassed on the use of the frequency response function method (FRF) applying the hammering method. The comparison between the numerical and experimental results proves that the suggested finite element models of the composite structural beams with bonded joints provide an efficient by accurate tool for the dynamic analysis of adhesive bonded joints. The damping capacity is inversely proportional to the stiffness of the bonded joint specimens. The type of the proportionality depends mainly on the bond line configuration type, lamina orientation, and boundary conditions. This in turn enables an accurate evaluation for selecting the proper characteristics of the specimens for controlling the present damping capacity and the proper resistance against deformation during the operating process. The present study provides an efficient non-destructive technique for the prediction of dynamic properties for an adhesive bonded joint for the studied composite structure systems. The coordination of the experimental and numerical techniques makes it possible to find an efficient tool for studying the dynamic performance of adhesively bonded joint for composite structures.

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Ultrasonic Welding of Novel Carbon/Elium® Thermoplastic Composites with Flat and Integrated Energy Directors: Lap Shear Characterisation and Fractographic Investigation

Materials ◽

10.3390/ma13071634 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1634 ◽

Cited By ~ 4

Author(s):

Somen K. Bhudolia ◽

Goram Gohel ◽

Jayaram Kantipudi ◽

Kah Fai Leong ◽

Robert J. Barsotti

Keyword(s):

Polymer Matrix Composites ◽

Research Work ◽

Ultrasonic Welding ◽

Industrial Applications ◽

Thermoplastic Composites ◽

Matrix Composites ◽

Thermoplastic Resin ◽

Lap Shear ◽

Weld Time ◽

Transfer Moulding

The current research work presents a first attempt to investigate the welding attributes of Elium® thermoplastic resin and the fusion bonding using ultrafast ultrasonic welding technique. The integrated energy director (ED) polymer-matrix composites (PMCs) panel manufacturing was carried out using the Resin Transfer Moulding (RTM) technique and the scheme is deduced to manufacture a bubble-free panel. Integrated ED configurations and flat specimens with Elium® film of different thickness at the interface were investigated for ultrasonic welding optimization. Optimised weld time for integrated ED and flat Elium® panels with film (0.5 mm thick) configuration was found to be 1 s and 5.5 s, respectively. The ED integrated configuration showed the best welding results with a lap shear strength of 18.68 MPa. The morphological assessment has shown significant plastic deformation of Elium® resin and the shear cusps formation, which enhances the welding strength. This research has the potential to open up an excellent and automated way of joining Elium® composite parts in automotive, wind turbines, sports, and many other industrial applications.

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Defects and uncertainties of adhesively bonded composite joints

SN Applied Sciences ◽

10.1007/s42452-021-04753-8 ◽

2021 ◽

Vol 3 (9) ◽

Author(s):

Sadik Omairey ◽

Nithin Jayasree ◽

Mihalis Kazilas

Keyword(s):

Composite Materials ◽

Composite Structures ◽

Production Efficiency ◽

Adhesive Bonding ◽

Detection Methods ◽

Bonded Joints ◽

Adhesively Bonded ◽

Adhesively Bonded Joints ◽

Wide Range ◽

Bonded Composite

AbstractThe increasing use of fibre reinforced polymer composite materials in a wide range of applications increases the use of similar and dissimilar joints. Traditional joining methods such as welding, mechanical fastening and riveting are challenging in composites due to their material properties, heterogeneous nature, and layup configuration. Adhesive bonding allows flexibility in materials selection and offers improved production efficiency from product design and manufacture to final assembly, enabling cost reduction. However, the performance of adhesively bonded composite structures cannot be fully verified by inspection and testing due to the unforeseen nature of defects and manufacturing uncertainties presented in this joining method. These uncertainties can manifest as kissing bonds, porosity and voids in the adhesive. As a result, the use of adhesively bonded joints is often constrained by conservative certification requirements, limiting the potential of composite materials in weight reduction, cost-saving, and performance. There is a need to identify these uncertainties and understand their effect when designing these adhesively bonded joints. This article aims to report and categorise these uncertainties, offering the reader a reliable and inclusive source to conduct further research, such as the development of probabilistic reliability-based design optimisation, sensitivity analysis, defect detection methods and process development.

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Static ultrasonic welding of carbon fibre unidirectional thermoplastic materials and the influence of heat generation and heat transfer

Journal of Composite Materials ◽

10.1177/0021998320976818 ◽

2021 ◽

pp. 002199832097681

Author(s):

F Köhler ◽

IF Villegas ◽

C Dransfeld ◽

A Herrmann

Keyword(s):

Cross Sections ◽

Weld Line ◽

Welding Process ◽

Ultrasonic Welding ◽

Thermoplastic Composites ◽

Squeeze Flow ◽

Anisotropic Flow ◽

Lap Shear ◽

Anisotropic Thermal Conductivity ◽

Edge Defects

Ultrasonic welding is a promising technology to join fibre-reinforced thermoplastic composites. While current studies are mostly limited to fabric materials the applicability to unidirectional materials, as found in aerospace structures, would offer opportunities for joining primary aircraft structures. However, due to the highly anisotropic flow of a molten unidirectional ply undesired squeeze flow phenomena can occur at the edges of the weld overlap. This paper investigates how the fibre orientation in the plies adjacent to the weld line influences the welding process and the appearance of edge defects. Ultrasonic welding experiments with different layups and energy director configurations were carried out while monitoring temperatures at different locations inside and outside the weld overlap. The joints were characterized by single lap shear tests, analysis of corresponding fracture surfaces and microscopic cross-sections. Results showed that the anisotropic flow and the anisotropic thermal conductivity of the plies adjacent to the weld line have a distinct effect on the appearance and location of edge defects. By using energy directors that cover only part of the weld overlap area a new approach was developed to mitigate edge defects caused by the highly directional properties of the unidirectional plies.

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Strength of adhesively bonded single-lap and lap-shear joints

International Journal of Solids and Structures ◽

10.1016/s0020-7683(97)00174-1 ◽

1998 ◽

Vol 35 (20) ◽

pp. 2601-2616 ◽

Cited By ~ 34

Author(s):

L. Tong

Keyword(s):

Adhesively Bonded ◽

Lap Shear

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Experimental Investigations on Aluminium Ultrasonic Welding Parameters

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.657.306 ◽

2014 ◽

Vol 657 ◽

pp. 306-310

Author(s):

Lăcrămioara Apetrei ◽

Vasile Rață ◽

Ruxandra Rață ◽

Elena Raluca Bulai

Keyword(s):

Microstructural Analysis ◽

Base Material ◽

Welding Process ◽

Ultrasonic Welding ◽

Experimental Investigations ◽

Welding Parameters ◽

Material Structure ◽

Welding Temperature ◽

Wide Range ◽

Made In

Research evolution timely tendencies, in the nonconventional technologies field, are: manufacture conditions optimization and complex equipments design. The increasing of ultrasonic machining use, in various technologies is due to the expanding need of a wide range materials and high quality manufacture standards in many activity fields. This paper present a experimental study made in order to analyze the welded zone material structure and welding quality. The effects of aluminium ultrasonic welding parameters such as relative energy, machining time, amplitude and working force were compared through traction tests values and microstructural analysis. Microhardness tests were, also, made in five different points, two in the base material and three in the welded zone, on each welded aluminium sample. The aluminum welding experiments were made at the National Research and Development Institute for Welding and Material Testing (ISIM) Timişoara. The ultrasonic welding temperature is lower than the aluminium melting temperature, that's so our experiments reveal that the aluminium ultrasonic welding process doesn't determine the appearance of moulding structure. In the joint we have only crystalline grains deformation, phase transformation and aluminium diffusion.

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