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1 – 10 of 301
Article
Publication date: 31 May 2013

Yongrong Wang and Peihua Zhang

This study aims to clarify the key factors among physical‐mechanical properties of fabrics in relation to the dynamic pressure performance of compression garment.

Abstract

Purpose

This study aims to clarify the key factors among physical‐mechanical properties of fabrics in relation to the dynamic pressure performance of compression garment.

Design/methodology/approach

The physical‐mechanical properties of 16 different fabrics were measured using a KESF standard evaluation system and INSTRON tensile tester, and the garment pressure was measured by dynamic pressure measuring system. Grey correlation analysis is used to determine the correlation degree of fabric physical‐mechanical properties and dynamic pressure magnitude.

Findings

The mechanical behaviors (e.g. tensile, shearing, and bending) and physical characteristics are different in elastic fabrics with varied content of elastic fiber, kinds of yarn, et al. Grey correlation analysis is a valid method to analyze the indices of a system, quantize them and put them in order. All the degrees of Grey correlation are more than 0.6. The degree of grey correlation between tensile force (F), shearing rigidity (G) and bending rigidity (B) are higher than others, hence it is conducted that these would significantly effect on garment pressure. The quantitative regression equations between pressure magnitude at extension of 50 percent and the individual key parameters (mean values in wale and course directions) of tested samples are illustrated.

Research limitations/implications

The other parameters (e.g. fabric structure, yarn fineness, and pre‐tension, et al.) should be taken into account. Further, an integrative mathematic model would be established, which could predict the garment pressure directly from the physical‐mechanical properties of fabric.

Originality/value

The present study indicates that pressure magnitude of elastic fabric is an integrative action performed by physical‐mechanical properties. The developed illustrative equations and method offer a rational and practical tool for assessing pressure functional performance of elastic fabric in the stages of design and product development.

Details

International Journal of Clothing Science and Technology, vol. 25 no. 2
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 16 January 2007

A. Kalendová and D. Veselý

This paper seeks to synthesize needle‐shaped anticorrosion pigments based on the ferrites of Zn, Ca and Mg for metal protecting paints.

1251

Abstract

Purpose

This paper seeks to synthesize needle‐shaped anticorrosion pigments based on the ferrites of Zn, Ca and Mg for metal protecting paints.

Design/methodology/approach

Anticorrosion pigments were synthesized from oxides or carbonates at hot temperatures. The following pigments were synthesized: ZnFe2O4, MgFe2O4, CaFe2O4, Mg0.2Zn0.8Fe2O4, and Ca0.2Zn0.8Fe2O4. The prepared pigments were characterized by means of X‐ray diffraction analysis, by measuring the distribution of particle size and by means of scanning electron microscopy. The synthesized anticorrosion pigments were used to formulate epoxy coatings with PVC = 10 per cent for the synthesized pigment and with the PVC/CPVC ratio = 0.3. The coatings were tested for physical‐mechanical properties and in corrosion atmospheres. The corrosion test results were compared with aluminium zinc phosphomolybdate.

Findings

The needle‐shaped particles were identified in the formulated pigments. It was found that all of the synthesized pigments had high anticorrosion efficiency comparable with that of Zn‐Al phosphomolybdate. The needle‐shaped particles markedly contributed to the advancement of the physical‐mechanical properties of epoxy coatings.

Practical implications

The synthesized pigments can be conveniently used in coatings protecting metal bases against corrosion.

Originality/value

The application of the synthesized pigments with the needle‐shaped particles in anticorrosion paints protecting metals presents a new method. The benefit of the application and method of synthesizing anticorrosion pigments is that they do not contain heavy metals and are acceptable for the environment.

Details

Anti-Corrosion Methods and Materials, vol. 54 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 2 August 2021

Abdelaziz Logbi, Mohamed Mani, Toufik Choungara and Abdelouahed Kriker

This paper aims to study the effect of mineral additions on the mortars’ physical, mechanical and durability properties. Two local mineral additions, considered inert, are chosen…

Abstract

Purpose

This paper aims to study the effect of mineral additions on the mortars’ physical, mechanical and durability properties. Two local mineral additions, considered inert, are chosen: limestone fillers from North-East of Algeria and natural dune sand from Algerian desert areas.

Design/methodology/approach

Two local additions are finely crushed to a fineness greater or equal to that of the used cement and incorporated into the mortars with predetermined rates; (0, 10%, 15% and 20%) compared to the cement weight to examine their effects on the mortars’ properties at different ages. Two conservation environments are chosen: freshwater as a neutral area and rising water table as an aggressive area to appreciate the effect of the two additions on physical and mechanical properties and durability.

Findings

The results showed the beneficial effect of these additions on compactness, mechanical resistance and durability toward the rising water table. The results have also allowed us to make an experimental comparison between the limestone addition which is commonly used in the Algerian cement industry and the dune sand, which is not yet well explored and exploited.

Originality/value

The added value of this study is the use of crushed dune sand which is a local addition of southern Algeria for improving the resistance of mortars and concrete toward the aggressiveness of rising water table which presents a major problem for the infrastructure of civil and public construction.

Details

World Journal of Engineering, vol. 20 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 17 June 2021

Fikrat Yusubov

The purpose of this paper is to investigate the influence of binder effect on tribological behavior of brake friction composite materials: a case study of phenolic resin modified…

Abstract

Purpose

The purpose of this paper is to investigate the influence of binder effect on tribological behavior of brake friction composite materials: a case study of phenolic resin modified by N-Methylaniline.

Design/methodology/approach

Four different friction materials have been fabricated by varying modified phenolic resin content. The samples were prepared by the conventional powder metallurgy methods following ball milling, mixing, pre-forming, hot pressing and post-curing processes. Thermogravimetric analysis was used to determination of the degradation mechanism of organic components and study of thermal stability of the samples. A friction test was carried out in dry conditions using a vertical tribometer. Analysis of worn surfaces was performed using a scanning electron microscope.

Findings

The experimental results revealed that the sample containing 25 Wt.% phenolic resin has good mechanical and thermal properties with stable friction characteristics.

Originality/value

This paper presents the effect of N-methylaniline modified phenolic resin on friction composites to improve tribological performance by its thermal properties.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 27 June 2022

Hicri Yavuz and Hüseyin Bayrakceken

The purpose of this paper, brake friction material samples with six different contents were produced using three different fiber types consisting of variable proportions of…

Abstract

Purpose

The purpose of this paper, brake friction material samples with six different contents were produced using three different fiber types consisting of variable proportions of huntite mineral and basalt, glass and steel fibers. The friction properties and formation of the transfer film in these friction materials were investigated.

Design/methodology/approach

Friction materials were produced using a hot molding method from materials containing 10%–15% huntite in varying proportions, consisting of basalt, glass and steel fibers. The densities and hardness values of the samples were measured. Friction tests were performed using a brake pad friction material tester to determine tribological properties. After the friction tests, microscopic examination of the sample surfaces was performed using scanning electron microscope (SEM) and three-dimensional (3D) surface profilometer devices.

Findings

Huntite mineral content and fiber type affected the friction coefficient. With an increase in the amount of huntite, the friction coefficient increased in the friction material samples formed with glass and steel fibers. The fiber type and amount of huntite also affected the transfer film formation. The surface roughness values of all the friction materials decreased with an increase in the amount of huntite. The surface roughness values of the samples with glass fibers were higher than those of other samples.

Originality/value

The importance of using huntite minerals and different fiber types in automotive brake friction materials is emphasized. This will help industrial companies and academics study the tribological properties of friction materials.

Details

Industrial Lubrication and Tribology, vol. 74 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 7 November 2016

Abolfazl Darvish, Reza Naderi and Mohammad Reza Mohammadzadeh Attar

This research aims to provide a comparative study of the effect of conventional zinc phosphate (ZP) and zinc aluminium phosphate (ZPA) representing second generation of…

Abstract

Purpose

This research aims to provide a comparative study of the effect of conventional zinc phosphate (ZP) and zinc aluminium phosphate (ZPA) representing second generation of phosphate-based anticorrosion pigments on the protective performance and physical mechanical properties of a solvent-borne polyurethane (PU) coating.

Design/methodology/approach

The two pigments were incorporated into the coating at optimum pigment volume concentration. To evaluate the protective performance, electrochemical impedance spectroscopy (EIS) was used. The effect of modification of ZP on the physical–mechanical properties of the coatings was studied through dynamic mechanical thermal analysis. Moreover, Micro Vickers hardness and pull-off tests were used to evaluate the hydrolytic coating degradation.

Findings

EIS revealed the superior protective function of coatings incorporated with ZPA compared to those formulated with ZP. This behaviour might be attributed to the release of sufficient inhibiting species because of partial dissolving of the anticorrosive pigments when an electrolyte penetrates into the coating. In addition, the effectiveness of modification of ZP on the physical–mechanical properties of coatings was shown.

Research limitations/implications

As a classical replacement for the toxic chromates, ZP has been widely used in the formulation of protective coatings. However, undesirable inhibitive function of the pigment arising from its low solubility has made modification necessary. Because of the modified solubility, second generation of phosphate-based anticorrosion pigments has been reported to reveal superior performance.

Originality/value

According to the literature, no report can be found studying the effect of the second generation of phosphate-based anticorrosion pigments on the physical–mechanical properties of PU coatings. The main goal of this work is to study the correlation between physical–mechanical properties and anticorrosion performance of the PU coatings.

Details

Pigment & Resin Technology, vol. 45 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 14 October 2021

Mohammed Seghir Ammari, Mohammed Bachir Tobchi, Yahia Amrani, Anouer Mim, Madani Bederina and Ahmida Ferhat

This study is part of the valorization of local materials and the reuse of industrial waste in construction. This study aims to improve the physical-mechanical properties of sand…

Abstract

Purpose

This study is part of the valorization of local materials and the reuse of industrial waste in construction. This study aims to improve the physical-mechanical properties of sand concrete. This work is a continuation of previous studies conducted on sand concrete, the purpose of which is to introduce industrial waste into this material. For this purpose, a glass waste in powder form is added.

Design/methodology/approach

This study is focused on the effect of adding glass powder (GP) whose mass percentage varies from 0 to 40% with an interval of 10% to target the right composition that ensures the best compromise between the characteristics studied.

Findings

The results found show that the workability and density of the studied concretes decreased with increasing GP dosage. Indeed, the optimal addition which constitutes the best compromise between the studied properties is 10% of GP. Improvements of up to about 9% in the case of flexural strength and about 18% in the case of compressive strength. The thermal conductivity has been reduced by 12.74%, the thermal diffusivity which characterizes the notion of thermal inertia has been reduced by about 4% and the specific heat mass has been reduced by 7.80%. Also, the shrinkage has been reduced by about 20%. The microstructure of the studied composite shows a good homogeneity between the aggregates. Finally, the addition of GP to sand concrete gives very encouraging results.

Originality/value

The interest of this study is in two parts. The first one is the exploitation of local materials: dune sand, river sand and limestone filler to meet the growing demand for construction materials. And the second one is the reuse of glass waste, in the form of powder (GP), to solve the environmental problem. All this participates in the improvement of the physical-mechanical properties of sand concrete and the extent of its response to the development of an economical structural concrete.

Details

World Journal of Engineering, vol. 20 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 March 2006

A. Kalendova, D. Veselý and P. Kalenda

To investigate the properties of coatings containing various types of fillers from the point of view of their physical‐mechanical properties and anticorrosive properties.

1549

Abstract

Purpose

To investigate the properties of coatings containing various types of fillers from the point of view of their physical‐mechanical properties and anticorrosive properties.

Design/methodology/approach

Research used fillers of different types varying in morphology and/or chemical composition; these were then compared with selected pigments and zinc phosphate, an anticorrosive pigment. The following parameters were observed for all of the fillers and pigments: oil absorption, CPVC value, density, extract pH, specific surface, particle size, and water‐soluble substances. The morphology of particles was observed by means of an electron‐scanning microscope. The coatings of these fillers and pigments were formulated on an epoxy resin binder basis cured with a polyamine hardener. The coatings prepared were subjected to the measurement of physical‐mechanical properties such as hardness and deepening resistance, flex resistance, adhesion to steel, and the gloss of the coatings. The coatings containing the fillers and pigments studied underwent corrosion tests in a condenser chamber and in a salt‐spray cabinet.

Findings

The results obtained through the tests allowed the selection of the optimum filler for an epoxy coating with barrier anticorrosive properties. As per respective findings, some fillers in these coatings of significant thickness can be comparable to their zinc phosphate counterparts.

Research limitations/implications

The anticorrosive properties of the coatings studied can also be tested in paints by means of atmospheric exposure, for instance, with the aid of a Florida test.

Practical implications

The findings are helpful towards applications in the formulations of anticorrosive coatings of significant thickness that offer an effective barrier mechanism.

Originality/value

The research presents the results of the properties of a whole range of industrially employed fillers and pigments contained in paints. Based on this study, the formulation of steel protecting coatings can be optimised.

Details

Pigment & Resin Technology, vol. 35 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 27 June 2008

A. Kalendová and D. Veselý

The purpose of this paper is to synthesize anticorrosion pigments ZnFe2O4 from diverse raw materials of various shapes and size of primary particles.

1360

Abstract

Purpose

The purpose of this paper is to synthesize anticorrosion pigments ZnFe2O4 from diverse raw materials of various shapes and size of primary particles.

Design/methodology/approach

Anticorrosion pigments were synthesized through a high‐temperature process during a solid phase. Zinc ferrites were prepared from hematite (α‐Fe2O3), goethite (α‐FeO.OH), magnetite (Fe3O4), and specularite (Fe2O3) entering into reaction with zinc oxide at temperatures ranging from 600 up to 1,100°C. The nature of the initial raw material, primarily the shape of its particles, affects the shape of the particles of the synthesized zinc ferrite. The formulated zinc ferrites had a rod‐shape, lamellar, and/or isometric shape. The shape of the particles of synthesized zinc ferrites was studied with regard to its effects on the mechanical and corrosion resistance of organic coatings. The obtained pigments were characterized by means of X‐ray diffraction analysis and scanning electron microscopy. The synthesized anticorrosion pigments were used to prepare epoxy coatings and water‐borne styrene‐acrylate coatings that were subjected to post‐application tests for physical‐mechanical properties and anticorrosion properties.

Findings

The shape of the particles was identified in the synthesized pigments. X‐ray diffraction analysis revealed the degree of precipitation and lattice parameters. All of the synthesized pigments had good anticorrosion efficiency in an epoxy and in styrene‐acrylate coatings. Compared with a commercially used anticorrosion pigment, their protective power in coatings was demonstrably stronger.

Practical implications

The synthesized pigments can be used conveniently in coatings protecting metal bases against corrosion.

Originality/value

The synthesis of zinc ferrites with different particle shapes for applications in anticorrosion coatings provides a new way of protecting metals against corrosion. Of benefit is the fact that the synthesized pigments do not contain any environmentally harmful substances.

Details

Anti-Corrosion Methods and Materials, vol. 55 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 16 January 2007

A. Kalendová, D. Veselý and P. Kalenda

The purpose of this paper is to synthesise X2TiO4 spinel‐type anticorrosion pigments and YTiO3, perovskite‐type anticorrosion pigments, where X = Zn, Mg, Ca, Sr; Y = Ca for metal…

Abstract

Purpose

The purpose of this paper is to synthesise X2TiO4 spinel‐type anticorrosion pigments and YTiO3, perovskite‐type anticorrosion pigments, where X = Zn, Mg, Ca, Sr; Y = Ca for metal protective paints.

Design/methodology/approach

Anticorrosion pigments were synthesised from oxides or carbonates at high temperature. The following pigments were synthesised: TiO2 · ZnO, 2TiO2 · ZnO, TiO2 · 2ZnO, TiO2 · MgO, TiO2 · CaO, TiO2 · ZnO · MgO, and TiO2 · ZnO · SrO. The pigments obtained were characterised by means of X‐ray diffraction analysis, measurement of particle sizes and scanning electron microscopy. The anticorrosion pigments synthesised were used to produce epoxy coatings with PVC = 10 per cent for each synthesised pigment. The coatings were tested for physical‐mechanical properties and in corrosion atmospheres. The corrosion test results were compared with those of alumino zinc phosphomolybdate.

Findings

A spinel or perovskite structure was found in the pigments synthesised. High anticorrosion efficiency was identified in all the synthesised pigments, the highest efficiency being demonstrated in the TiO2 · ZnO pigment of spinel structure and in the TiO2 · CaO pigment of perovskite structure.

Practical implications

The pigments synthesised can be conveniently used to protect metal bases from corrosion.

Originality/value

The use of pigments synthesised in anticorrosion coatings for metal protection presents a new approach. Its benefits are the use and the method of synthesising the anticorrosion pigments that do not contain heavy metals and that are acceptable for the environment.

Details

Pigment & Resin Technology, vol. 36 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of 301