• Title/Summary/Keyword: interface adhesion

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Estimation of Interfacial Adhesion through the Micromechanical Analysis of Failure Mechanisms in DLC Film

  • Jeong, Jeung-Hyun;Park, Hae-Seok;Ahn, Jeong-Hoon;Dongil Kwon
    • The Korean Journal of Ceramics
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    • v.3 no.2
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    • pp.73-81
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    • 1997
  • In this paper, it is intended to present more reproducible and quantitative method for adhesion assemssement. In scratch test, micromechanical analysis on the stress state beneath the indenter was carried out considering the additional blister field. The interface adhesion was quantified as work of adhesion through Griffith energy approach on the basis of the analyzed stress state. The work of adhesion for DLC film/WC-Co substrate calculated through the proposed analysis shows the identical value regardless of distinctly different critical loads measured with the change of film thickness and scratching speed. On the other hand, uniaxial loading was imposed on DCL film/Al substrate, developing the transverse film cracks perpendicular to loading direction. Since this film cracking behavior depends on the relative magnitude of adhesion strength to film fracture strength, the quantification of adhesion strength was given a trial through the micromechanical analysis of adhesion-dependence of film cracking patterns. The interface shear strength can be quantified from the measurement of strain $\varepsilon$s and crack spacing $\lambda$ at the cessation of film cracking.

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Adhesion between Rubber Compound and Copper-Film-Coated Steel Plate Prepared by Vacuum Sputtering and Substitution Plating Methods (진공증착법과 치환도금법으로 제조한 구리박막 피복철판과 배합고무의 접착)

  • Moon, Kyung-Ho;Han, Min-Hyun;Seo, Gon
    • Journal of Adhesion and Interface
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    • v.4 no.3
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    • pp.1-8
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    • 2003
  • Adhesion between rubber compound and copper-film-coated steel plate (abbreviated hereafter as copper film plate) with different thicknesses of copper film was investigated. Two different methods were employed for the preparation of the copper film plates: a substitution plating of preelectroplated zinc with copper ion and a vacuum sputtering of copper on steel plate. Adhesion strength of the copper film plates with rubber compounds was largely dependent upon the thickness of copper film, regardless of their preparation methods. The copper film plates with thinner thickness than 75 nm showed high adhesion comparable to brass, while those with thicker copper film showed poor adhesion due to excessive growth of copper sulfide at adhesion interface.

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Hot AC Anodising as a Cr(VI)-free Pre-treatment for Structural Bonding of Aluminium

  • Lapique, Fabrice;Bjorgum, Astrid;Johnsen, Bernt;Walmsley, John
    • Journal of Adhesion and Interface
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    • v.4 no.2
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    • pp.21-29
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    • 2003
  • Hot AC anodising has been evaluated us pre-treatment for aluminium prior to structural adhesive bonding. Phosphoric and sulphuric acid hot AC anodising showed very promising adhesion promoter capabilities with durability comparable with the best standard DC anodising procedures. AC anodising does not required etching prior to anodising and offers u pre-treatment time down to 20 seconds. The interface/interphase between the aluminium substrate and the adhesive was investigated in order to get a better understanding of the involved adhesion mechanisms and to explain the long-tenn properties. The alkaline medium formed at the oxide layer/adhesive interface has been shown to induce a partial dissolution of the oxide layer leading to the formation of metallic ions which diffuse in the adhesive (EPMA measurements). The effect of diffusion of the Al ions on adhesion and joint durability is still uncertain but studies showed that pre-bond moisture affected the joints durability and to some extent the diffusion length. specially for DC anodised samples. So far no direct correlation could be established between the diffusion length d and the joints durability but new trials with better control over the elapsed time between bonding and adhesive curing are expected to help getting a better understanding of the involved mechanisms.

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A Molecular Simulation on the Adhesion Control of Metal Thin Film-Carbon Nanotube Interface based on Thermal Wetting (Thermal wetting 현상이 탄소나노튜브-금속박막 계면의 응착력에 미치는 영향에 관한 분자 시뮬레이션 연구)

  • Sang-Hoon Lee;Hyun-Joon Kim
    • Tribology and Lubricants
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    • v.39 no.1
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    • pp.8-12
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    • 2023
  • This study presents a molecular simulation of adhesion control between carbon nanotube (CNT) and Ag thin film deposited on silicon substrate. Rough and flat Ag thin film models were prepared to investigate the effect of surface roughness on adhesion force. Heat treatment was applied to the models to modify the adhesion characteristics of the Ag/CNT interface based on thermal wetting. Simulation results showed that the heat treatment altered the Ag thin film morphology by thermal wetting, causing an increase in contact area of Ag/CNT interface and the adhesion force for both the flat and rough models changed. Despite the increase in contact area, the adhesion force of flat Ag/CNT interface decreased after the heat treatment because of plastic deformation of the Ag thin film. The result suggests that internal stress of the CNT induced by the substrate deformation contributes in reduction of adhesion. Contrarily, heat treatment to the rough model increases adhesion force because of the expanded contact area. The contact area is speculated to be more influential to the adhesion force rather than the internal stress of the CNT on the rough Ag thin film, because the CNT on the rough model contains internal stress regardless of the heat treatment. Therefore, as demonstrated by simulation results, the heat treatment can prevent delamination or wear of CNT coating on a rough metallic substrate by thermal wetting phenomena.