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Article
Publication date: 17 June 2020

Jiawei Wang, Jinliang Liu, Guanhua Zhang and Jigang Han

Considering the “size effect” and the properties degradation of building materials on the strengthened engineering, in this paper, the technology of pasting steel plate

Abstract

Purpose

Considering the “size effect” and the properties degradation of building materials on the strengthened engineering, in this paper, the technology of pasting steel plate was adopted to shear strengthen a 16 m prestressed concrete hollow slab, which had serviced 20 years in cold regions. The shear properties of shear strengthen beams are analyzed.

Design/methodology/approach

Shear loading test of the shear strengthened beam and the contrast beam was conducted. Then the mechanical characteristics, failure mechanism, the mechanical response and shear capacity of shear strengthened beam and contrast beam had been discussed.

Findings

The failure mode of shear strengthened beam and contrast beam was shear compression failure, and the bond failure between concrete and prestressed reinforcement happened in both of test beams. The shear strengthening method of pasting steel plate can effectively improve the mechanical response for the shear strengthened beam. Compared with the contrast beam, the cracking load and failure shear capacity for the shear strengthened beam can be effectively increased by 12.2 and 27.6%, respectively.

Originality/value

The research results can be a reference for the detection and evaluation of shear strengthened bridges, which are strengthened by pasting steel plate. Engineers can refer to the shear strengthening method in this paper to strengthen the existing bridge, which can guarantee the safety of shear strengthened bridges.

Details

International Journal of Structural Integrity, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 23 October 2020

Jiaqiang Chen

The main supporting frame of steel structure buildings is steel, and the beam-column joints of the steel structure directly affect the stability and strength of the…

Abstract

Purpose

The main supporting frame of steel structure buildings is steel, and the beam-column joints of the steel structure directly affect the stability and strength of the supporting frame.

Design/methodology/approach

This paper briefly introduced the beam-column joints which are used for ensuring the stability of buildings in the steel structure building, selected the fabricated beam-column joints which were different from the traditional welding methods, tested the fabricated beam-column joints with the reaction frame and jack and detected the influence of the thickness and length of the splice plate on the mechanical properties of joints.

Findings

The results showed that the joint stress and the displacement in the vertical direction increased under greater load no matter which kind of fabricated joint was used; under the same load, the thickness and length of the splice significantly affected the mechanical properties of joints, and the larger the thickness and length, the smaller the joint stress and displacement in the vertical direction.

Originality/value

To sum up, increasing the thickness or length of the splice plate of the fabricated joint can effectively improve the mechanical properties of joints.

Details

International Journal of Building Pathology and Adaptation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2398-4708

Keywords

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Article
Publication date: 1 March 1991

M. Lahdenperä

In this research work thick‐film manufacturing technology on stainless steel baseplates was developed. Adequate adhesion of dielectric IP211 to the steel substrate was…

Abstract

In this research work thick‐film manufacturing technology on stainless steel baseplates was developed. Adequate adhesion of dielectric IP211 to the steel substrate was achieved only by sand blast roughening. Standard PdAg thick‐film conductors were not solderable to IP211. The solution was to have a separate multilayer dielectric under conductors to be soldered. The reliability of soft soldering and gold wire bonding of thick‐film metallisation on stainless steel and other baseplate materials was evaluated. The technology developed was applied to manufacturing an intelligent signal node. Present expertise enables the manufacture of thick‐film hybrids on stainless steel baseplates. Development of an industrial production line would, however, involve considerable effort.

Details

Microelectronics International, vol. 8 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 11 April 2008

S. Mallik, N.N. Ekere, R. Durairaj and A.E. Marks

The purpose of this paper is to investigate the rheological behaviour of three different lead‐free solder pastes used for surface mount applications in the electronic industry.

Abstract

Purpose

The purpose of this paper is to investigate the rheological behaviour of three different lead‐free solder pastes used for surface mount applications in the electronic industry.

Design/methodology/approach

This study concerns the rheological measurements of solder paste samples and is made up of three parts. The first part deals with the measurement of rhelogical properties with three different measuring geometries, the second part looks into the effect of frequencies on oscillatory stress sweep measurements and the final part reports on the characterisation and comparison of three different types of Pb‐free solder pastes.

Findings

Among the three geometries, the serrated parallel plate was found effective in minimising the wall‐slip effect. From the oscillatory stress‐sweep data with different frequencies; it was observed that the linear visco‐elastic region is independent of frequency for all the solder paste samples. To understand the shear thinning behaviour of solder paste, the well known Cross and Carreau models were fitted to the viscosity data. Moreover, creep‐recovery and dynamic frequency‐sweep tests were also carried out without destroying the sample's structure and have yielded useful information on the pastes behaviour.

Research limitations/implications

More extensive research is needed to fully characterise the wall‐slip behaviour during the rheological measurements of solder pastes.

Practical implications

The rheological test results presented in this paper will be of important value for research and development, quality control and facilitation of the manufacturing of solder pastes and flux mediums.

Originality/value

This paper shows how wall‐slip effects can be effectively avoided during rheological measurements of solder pastes. The paper also outlines how different rheological test methods can be used to characterise solder paste behaviours.

Details

Soldering & Surface Mount Technology, vol. 20 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 1 November 1962

Geigy Co. Ltd. Stand 75. Diversified application of benzotriazole as a corrosion inhibitor specifically for copper and its alloys is the main theme of Geigy's stand.

Abstract

Geigy Co. Ltd. Stand 75. Diversified application of benzotriazole as a corrosion inhibitor specifically for copper and its alloys is the main theme of Geigy's stand.

Details

Anti-Corrosion Methods and Materials, vol. 9 no. 11
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 3 February 2012

Robert Kay and Marc Desmulliez

The purpose of this paper is to present a detailed overview of the current stencil printing process for microelectronic packaging.

Abstract

Purpose

The purpose of this paper is to present a detailed overview of the current stencil printing process for microelectronic packaging.

Design/methodology/approach

This paper gives a thorough review of stencil printing for electronic packaging including the current state of the art.

Findings

This article explains the different stencil technologies and printing materials. It then examines the various factors that determine the outcome of a successful printing process, including printing parameters, materials, apparatus and squeegees. Relevant technical innovations in the art of stencil printing for microelectronics packaging are examined as each part of the printing process is explained.

Originality/value

Stencil printing is currently the cheapest and highest throughput technique to create the mechanical and electrically conductive connections between substrates, bare die, packaged chips and discrete components. As a result, this process is used extensively in the electronic packaging industry and therefore such a review paper should be of interest to a large selection of the electronics interconnect and assembly community.

Details

Soldering & Surface Mount Technology, vol. 24 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 1 August 1997

D. Mukherjee

Metallic finishing of materials, unlike non‐metallic finishing, comprises various popular surface modification processes, e.g. electroplating, conversion coating…

Abstract

Metallic finishing of materials, unlike non‐metallic finishing, comprises various popular surface modification processes, e.g. electroplating, conversion coating, anodizing, metal spraying, hot dip coating and also diffusion coatings. Diffusion coatings on metallic substrates are well known for their better abrasion resistance and adhesion to the substrate. Resistance to corrosion may also be incorporated on these surfaces by the addition of appropriate dopant elements like Cr, Ni and Al. However, these diffusion alloy‐layers are more sought after for functional properties than their aesthetic look. It appears that the concept of functional metal finishing is gaining ground for its longer service‐life and better performance. Discusses some of these aspects of diffusion alloy coatings on mild steel substrate and analyses their comparative merits and demerits. In this connection, three distinctly different types of barrier layers, namely, hard diffusion alloy layer, e.g. chromiding, Ni‐Cr diffusion coatings and soft‐diffusion layer, e.g. Pb‐Cd, Zn‐Sn barriers and those in between, e.g. hot dip zinc‐alloy coated barrier layers, have been highlighted for their corrosion resistance properties.

Details

Anti-Corrosion Methods and Materials, vol. 44 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 1 December 2004

Janusz Sitek, Dubravka Ročak, Krystyna Bukat, Janeta Fajfar‐Plut and Darko Belavič

The European Commission has decided that from the second half of 2006 only lead‐free solder pastes will be permitted for use in the electronics industry. Earlier results…

Abstract

The European Commission has decided that from the second half of 2006 only lead‐free solder pastes will be permitted for use in the electronics industry. Earlier results of testing showed that lead‐free solder pastes may not be appropriate for both printed‐circuit‐board (PCB) and hybrid‐circuit applications, because of the materials' compatibility with the soldering process and with the solder pads. The basic properties of the investigated pastes show which of the tested solder pastes can be used for both applications. After selection of the appropriate solder pastes, reliability tests were conducted. The surface insulation resistance was tested for both the hybrid circuits and PCBs, whereas the mechanical strength of the soldered joints of components was only tested for the PCBs.

Details

Soldering & Surface Mount Technology, vol. 16 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 1 August 1954

A powder form of polythene has been developed by the Telegraph Construction & Maintenance Co. Ltd. which can be applied to metal to give a smooth coating of plastic for…

Abstract

A powder form of polythene has been developed by the Telegraph Construction & Maintenance Co. Ltd. which can be applied to metal to give a smooth coating of plastic for protective, insulation or decorative purposes. Examples of the use of this material, known as Telcothene powder, as a protective coating includes electro‐plating jigs, metal containers and small tanks used for the storage or transport of corrosive liquids or pastes, stirring equipment for the chemical industry, and coated wire screen likely to come in contact with or be immersed in corrosive liquids.

Details

Anti-Corrosion Methods and Materials, vol. 1 no. 8
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 August 1998

Jaroslav Mackerle

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder…

Abstract

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

Details

Engineering Computations, vol. 15 no. 5
Type: Research Article
ISSN: 0264-4401

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