This paper aims to study the effect of SiO2 nano‐particulates on the corrosion behaviour of Ni‐W/SiO2 nanocomposite coatings.
Abstract
Purpose
This paper aims to study the effect of SiO2 nano‐particulates on the corrosion behaviour of Ni‐W/SiO2 nanocomposite coatings.
Design/methodology/approach
Weight loss measurements, electrochemical measurements and scanning electron microscope were used to study the corrosion behaviour of Ni‐W/SiO2 nanocomposite coatings in NaCl solution.
Findings
The incorporation of SiO2 nano‐particulates into the Ni‐W alloy matrix significantly increased the corrosion resistance. The improvement in corrosion resistance was due to the SiO2 nano‐particulates acting as physical barriers to the corrosion process by filling in crevices, gaps and microscopic holes on the surface of the Ni‐W alloy.
Originality/value
This study highlights the use of nano‐particulates for the control of Ni‐W alloy coating corrosion and opens a new route for industry in the anti‐corrosion field.
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Andrea Lucherini and Donatella de Silva
Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings…
Abstract
Purpose
Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings are particularly complex materials to be modelled and predicted, which can be extremely useful especially for performance-based fire safety designs. In addition, many parameters influence their performance, and this challenges the definition and quantification of their material properties. Several approaches and models of various complexities are proposed in the literature, and they are reviewed and analysed in a critical literature review.
Design/methodology/approach
Analytical, finite-difference and finite-element methods for modelling intumescent coatings are compared, followed by the definition and quantification of the main physical, thermal, and optical properties of intumescent coatings: swelled thickness, thermal conductivity and resistance, density, specific heat capacity, and emissivity/absorptivity.
Findings
The study highlights the scarce consideration of key influencing factors on the material properties, and the tendency to simplify the problem into effective thermo-physical properties, such as effective thermal conductivity. As a conclusion, the literature review underlines the lack of homogenisation of modelling approaches and material properties, as well as the need for a universal modelling method that can generally simulate the performance of intumescent coatings, combine the large amount of published experimental data, and reliably produce fire-safe performance-based designs.
Research limitations/implications
Due to their limited applicability, high complexity and little comparability, the presented literature review does not focus on analysing and comparing different multi-component models, constituted of many model-specific input parameters. On the contrary, the presented literature review compares various approaches, models and thermo-physical properties which primarily focusses on solving the heat transfer problem through swelling intumescent systems.
Originality/value
The presented literature review analyses and discusses the various modelling approaches to describe and predict the behaviour of swelling intumescent coatings as fire protection for structural materials. Due to the vast variety of available commercial products and potential testing conditions, these data are rarely compared and combined to achieve an overall understanding on the response of intumescent coatings as fire protection measure. The study highlights the lack of information and homogenisation of various modelling approaches, and it underlines the research needs about several aspects related to the intumescent coating behaviour modelling, also providing some useful suggestions for future studies.
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Abstract
Purpose
This paper aims to introduce a novel approach to the fabrication of photoluminescent materials by coating rare earth aluminate luminescent materials on metallic substrates and a readily manufacturable light source with robust structure in the form of photoluminescent sphere (APS).
Design/methodology/approach
The clean and dried stainless steel sphere was sprayed with UH 2593, a white undercoat, the luminescent coating and the weather resistance coating in chronological order.
Findings
After adhered onto the stainless steel sphere, the peaks corresponding to the N-H stretching vibrations were changed. The intensity of free N-H stretching at 3,536 cm−1 dramatically decreased and the peak of hydrogen-bonded N-H stretching of PU moved to lower wavenumbers. The red shift of the infrared bands of functional groups was attributed to the strengthened hydrogen bonding. The hydrogen bonding interactions between the stainless steel substrates and the polyurethane coating endowed the APS with excellent adhesive property and also promoted the evenly distribution of the photoluminescent particles in the polymer coating matrix.
Practical implications
This approach can be applicable in the fabrication of the photoluminescent materials. The APS can be used as signs and guiding post in remote areas without sufficient electricity supply and in the seas and rivers with complicated hydrological conditions.
Originality/value
This approach has provided a method to produce tough and durable luminescent signs for remote areas and dangerous seas and explained the functional mechanism of the combined application of metallic materials and non-metallic materials.
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Ramakant Rana, Qasim Murtaza and R.S. Walia
In this study, the tri-bological behaviour of the un-coated and diamond coated tungsten carbide was evaluated using the pin-on-disc test rig. The same was also tested on a lathe…
Abstract
Purpose
In this study, the tri-bological behaviour of the un-coated and diamond coated tungsten carbide was evaluated using the pin-on-disc test rig. The same was also tested on a lathe machine tool. This paper aims to compare the tri-bological behaviour of coated tungsten carbide pin with un-coated tungsten carbide pin it also correlates the wear obtained from the two machines used.
Design/methodology/approach
Experiments were performed using L8 orthogonal array and results obtained on a pin-on-disc test rig under dry sliding process were optimized through a modern optimization technique i.e. genetic algorithm (GA). The response surface methodology model (L8 orthogonal array) formed the basis for the development of the GA model, which defines the conditions of minimum wear, minimum coefficient of friction and minimum surface roughness for the sliding process of the pin-on-disc test rig.
Findings
Implementation of the heuristic approach for optimization of input parameters for the combination of tool material used for the turning process. The initial approach involves tri-bological testing considering the same combination. The set of experiments further performed, inferred that the results were similar and that the diamond coating enhances the life of the tool.
Originality/value
Successfully synthesized the diamond coating on tungsten carbide tool material. Implantation of the heuristic approach, i.e. GA to tri-bological tests to identify the optimized level of input variables. Experimentation involves the tri-bological testing whose results were confirmed through performing experiments on the lathe machine tool.
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The coatings industry, as well as the chemical industry of which it is a part, is being subjected to stress. There are numerous ways to react to stress. One way to react to stress…
Abstract
The coatings industry, as well as the chemical industry of which it is a part, is being subjected to stress. There are numerous ways to react to stress. One way to react to stress is to prognosticate, and the coatings industry has not been without those who wish to forecast its future. To attempt to delve into the future is both interesting and important and, accordingly, in this report we shall examine some of these forecasts. But first let us review briefly the origin of the stress to which the coatings industry is being subjected.
L. Mathivanan and S. Radhakrishna
Describes the preparation and properties of heat‐resistant paints based on an epoxy blended with rhodorsil silicone resin. Studies the heat‐resistant properties as per ASTM…
Abstract
Describes the preparation and properties of heat‐resistant paints based on an epoxy blended with rhodorsil silicone resin. Studies the heat‐resistant properties as per ASTM standard (D 2485‐91). Also determines the properties of the liquid paint and coated metal panels. Assesses the thermal degradation of the coating both by electrochemical (potential vs time and EIS) and structural (SEM) means. Results reveal that the coating is stable up to 200°C on a mild steel surface and degradation takes place only beyond this temperature. Discusses the failure mechanism of the above coating in light of the experiment’s results.
This paper is an initial attempt to discuss the American institutionalist movement as it changed and developed after 1945. Institutionalism in the inter-war period was a…
Abstract
This paper is an initial attempt to discuss the American institutionalist movement as it changed and developed after 1945. Institutionalism in the inter-war period was a relatively coherent movement held together by a set of general methodological, theoretical, and ideological commitments (Rutherford, 2011). Although institutionalism always had its critics, it came under increased attack in the 1940s, and faced challenges from Keynesian economics, a revived neoclassicism, econometrics, and from new methodological approaches derived from various versions of positivism. The institutionalist response to these criticisms, and particularly the criticism that institutionalism “lacked theory,” is to be found in a variety of attempts to redefine institutionalism in new theoretical or methodological terms. Perhaps the most important of these is to be found in Clarence Ayres’ The Theory of Economic Progress (1944), although there were many others. These developments were accompanied by a significant amount of debate, disagreement, and uncertainty over future directions. Some of this is reflected in the early history of The Association for Evolutionary Economics.
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A review essay on Ivo Maes, Economic Thought and the Making of European Monetary Union: Selected Essays of Ivo Maes, with forewords by Guy Quaden and A. W. Coats, Cheltenham…
Abstract
A review essay on Ivo Maes, Economic Thought and the Making of European Monetary Union: Selected Essays of Ivo Maes, with forewords by Guy Quaden and A. W. Coats, Cheltenham, U.K., and Northampton, MA: Edward Elgar Publishing. ISBN 1 84064 800 7, hardcover, 2002. European economic integration, leading to the Single Market and at the start of 1999 to the replacement of eleven national currencies by the euro, remains tumultuous, with France and Germany exempting themselves in November 2003 from the budget deficit limits of the Economic Growth and Stability Pact (the Maastricht Treaty), which had been binding on less politically powerful countries such as Portugal. Ivo Maes is ideally suited to provide insight and perspective on the economic thought underlying these developments. As Deputy Head of the Research Department of the National Bank of Belgium and formerly an administrator (that is, a generalist rather than a specialist economist) with the Commission of the European Communities, he is a central bank insider whose book carries a foreword by Guy Quaden, Governor of the National Bank of Belgium, and concludes with a long essay written with Jan Smets, Director of the Research Department of the National Bank of Belgium and Commissioner-General for the Euro, and Jan Michielsen, formerly Head of the Foreign and Financial Market Departments of the National Bank of Belgium. In Part 3, Maes, Smets, and Michielsen argue that Belgium played a leading role in shaping the Economic and Monetary Union (EMU) and especially in promoting Franco-German agreement. At the same time, Maes can view the monetary authorities as an academic outsider, a professor at the University of Leuven and at the ICHEC business school in Brussels, a sometime visiting professor at Texas Lutheran College and Duke University, and a respected historian of economics. His Brussels vantage point, in a city and country particularly closely engaged in the evolution of the European Community but not in one of the major powers within the Community, also contributes to an enlightening perspective. There has been a torrent of books on the politics and economics of the euro (e.g. Padoa-Schioppa, 1994), as well as specialist periodicals such as the Journal of Common Market Studies, but Maes stands out by considering the process as an historian of economics.
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This article attempts to tackle a fundamental methodological question in economics. The task is to investigate whether competing traditions in the history of economics are…
Abstract
This article attempts to tackle a fundamental methodological question in economics. The task is to investigate whether competing traditions in the history of economics are commensurable or not, that is, whether there is a firm ground on which a researcher could adjudicate the truth content of a theory. Thomas Kuhn in philosophy and Donald McClosky in economics among others are understood to advance the thesis that theories are incommensurable since there is no empirical ground to resort to in order to resolve disputes among traditions in economics. Karl Popper in philosophy and Mark Blaug in economics among others argue that theories are commensurable since there is a sharp and distinct criterion which could determine the scientific content of a theory. A more sophisticated version of Popper's falsificationism has been advanced in philosophy by Imre Lakatos and has been correspondingly followed in economics by Spiro Latsis, E. Roy Weintraub and others.