Use of intumescent flame-retardant systems in epoxy adhesives for debonding purpose

Heliyon, Journal Year: 2024, Volume and Issue: 10(3), P. e25240 - e25240

Published: Jan. 28, 2024

This work investigates the use of intumescent flame-retardant additives as a new debonding solution to disassemble bonded aluminum substrates. Melamine polyphosphate (MPP) or ammonium (APP) was incorporated into an epoxy adhesive joint both acid source and swelling agent with this stimulus responsive behavior being triggered by heating. The ability system containing swell foam under heat radiation efficiently exploited provide enough local pressure induce porosities cracks at interface, facilitating disassembling Several aluminum/intumescent-epoxy/aluminum laminates were assembled tested assess influence MPP APP content on mechanical strength joints. structural, morphological, mechanical, thermal properties these modified resins assemblies substrates studied using Scanning Electron Microscopy (SEM), pull-off test, Differential Calorimetry (DSC), Thermogravimetric Analysis (TGA). intumescent-modified joints support temperature-controlled evaluated oven. lower temperatures found comparable unmodified systems. Our patented on-demand technology, based system, represents promising treatment for multi-material structures will enable products be recycled end their service life.

Language: Английский

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Detecting and assessing weak adhesion in structural single lap joints using a machine learning pipeline with lamb waves data

Neural Computing and Applications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 4, 2025

Language: Английский

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The effects of material type and temperature factors on the adhesive bonding strength of 3D printed multi-material plastic structures

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications, Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 30, 2024

In this study, various test samples were produced using PLA based two filament materials with different fillers (2% calcium carbonate containing polylactic acid / Plus and 15% carbon fiber-reinforced CF) infill ratios (50% 100%), in both single-material multi-material forms. Adhesive joints of formed under environmental conditions (room temperature −25°C). The effects changes on the adhesive bonding strength investigated. For purpose, mechanical tests conducted single lap conditioned at room (unconditioned) −25°C for 5 days (exposed 120 h). reaction values parts to varies depending material type ratio. On other hand, multi-materials, regardless ratio, obtained are 11%-36% higher than those specimens cold temperatures. conditions, it was observed that creating from CF-CF surfaces multi-materials provided highest strength. This study examines properties (tensile hardness) multi materials, performance these joints. 4.14 MPa found 100% ratio lowest 2.05 PP-PP 50% −25°C.

Language: Английский

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Damage Metrics for Void Detection in Adhesive Single-Lap Joints

Mathematics, Journal Year: 2023, Volume and Issue: 11(19), P. 4127 - 4127

Published: Sept. 29, 2023

Structural Health Monitoring (SHM) techniques, such as Electromechanical Impedance Spectroscopy (EMIS), aim to continuously monitor structures for defects, thus avoiding the need regular maintenance. While attention has been given application of EMIS in automatic detection damage metallic and composite components, integrity monitoring structural adhesive joints comparatively neglected. This paper investigated use metrics with electrical impedance measurements detect defects Single-Lap Joints (SLJs) bonded a modified epoxy adhesive. Traditional using statistical distance-based concepts, Root-Mean-Squared Deviation, RMSD, or Correlation Coefficient, CC, are addressed at detecting voids layer applied five different spectral frequency ranges. Furthermore, new have developed, Average Canberra Distance, ACD, which enables reduction possible outliers detection, complex cRMSD, allows both real imaginary components impedance, enabling better joints. Overall, is achieved, certain conditions, differentiation between sizes, specific metrics, RMSD may be possible. cRMSD values from damaged SLJs tend double metric undamaged

Language: Английский

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Characterization of Densified Pine Wood and a Zero-Thickness Bio-Based Adhesive for Eco-Friendly Structural Applications

Materials, Journal Year: 2023, Volume and Issue: 16(22), P. 7147 - 7147

Published: Nov. 13, 2023

This study investigates a sustainable alternative for composites and adhesives in high-performance industries like civil automotive. pioneers the development application of new methodology to characterize bio-based, zero-thickness adhesive. method facilitates precise measurements adhesive’s strength fracture properties under conditions. The research also encompasses characterization densified pine wood, an innovative wood product distinguished by enhanced mechanical properties, which is subsequently compared natural wood. We conducted comprehensive wood’s utilizing dogbone-shaped samples fiber direction, block specimens transverse direction. Butt joints were employed adhesive testing. Mode I determined via compact tension (CT) double cantilever beam (DCB) tests adhesive, respectively, while mode II response was assessed through end-loaded split (ELS) tests. densification procedure, encompassing chemical processes, focal point study. Initially, subjected acid boiling remove matrix, followed pressure enhance density. As result, density increased approximately 100 percent, accompanied substantial improvements energy along direction about 120 percent. However, it worth noting that due delignification nature method, mainly reliant on lignin exhibited compromises. Also introduced technique evaluate bio-based applied as layer. results from this reveal promising highlighting potential eco-friendly substitute synthetic industry.

Language: Английский

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