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Article
Publication date: 12 December 2018

Wuman Zhang, Jingsong Zhang and Shuhang Chen

Ethylene glycol (EG) solution is a common deicing fluid of the aircrafts. Roller compacted concrete (RCC) used in the runway and the parking apron will be subjected to freeze-thaw…

Abstract

Purpose

Ethylene glycol (EG) solution is a common deicing fluid of the aircrafts. Roller compacted concrete (RCC) used in the runway and the parking apron will be subjected to freeze-thaw cycles in EG solution. The purpose of this study is to find whether RCC can be damaged by the action of freeze-thaw cycles or long-term immersion in EG solution.

Design/methodology/approach

Freeze-thaw cycles test and immersion test in EG solution by weight were used to accelerate the degradation of RCC. A compression test and a three-point bending test were carried out in the laboratory to evaluate mechanical properties of RCC. The changes of microstructure were monitored by using scanning electron microscopy and energy-dispersive X-ray analysis.

Findings

The results show that RCC specimens have little weight change in both freeze-thaw cycles test and immersion test. The dynamic modulus of elasticity, the compressive strength and the flexural strength of RCC with 250 freeze-thaw cycles in EG solution are decreased by 4.2, 15 and 39 per cent, respectively. The compressive strength is decreased by 35 per cent after 12 months of immersion in EG solution. Micro-cracks occur and increase with the increase in freeze-thaw cycles and immersion test.

Originality/value

The mass ratio of the elements in the crystal is very close to the proportion of elements in CaC2O4 (C:O:Ca = 1:1.26:1.6). More attention should be paid to using EG in practical engineering because both the freeze-thaw cycles and the complete immersion in EG solution damage the mechanical properties of RCC.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 3 July 2023

Yupeng Mou, Jiao Fan, Zhihua Ding and Inayat Khan

In order to encourage customers to try experience virtual tourism, researchers and practitioners pay more attention on how to improve customers' perception of authenticity.

Abstract

Purpose

In order to encourage customers to try experience virtual tourism, researchers and practitioners pay more attention on how to improve customers' perception of authenticity.

Design/methodology/approach

Using the theory of cross-sensory compensation, through 4 experiments, this study examines the impact of social interaction and cross-sensory strategies on the relationship between virtual reality (VR) and improving customers' perception of authenticity and customer experience.

Findings

Through experimental research, this paper finds that (1) VR immersion has a significant positive impact on perception of authenticity, which in turn acts on customers' virtual tourism experience. (2) In addition, social interaction strengthens the relationship between VR immersion and customers' perception of authenticity. (3) The cross-sensory compensation has a positive effect on VR immersion to enhance customers' perception of authenticity.

Originality/value

The research conclusion provides a direction for further discussion on how to improve customers' perception of authenticity and provides theoretical guidance and reference for the virtual tourism industry.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 36 no. 1
Type: Research Article
ISSN: 1355-5855

Keywords

Article
Publication date: 1 June 1991

C. Wrubl, A. Mollica, U. Montini and A. Litigio

The salt‐spray test is still today often utilized to control the anticorrosive performance of paints applied on metallic substrates. The time required for this test method is much…

Abstract

The salt‐spray test is still today often utilized to control the anticorrosive performance of paints applied on metallic substrates. The time required for this test method is much shorter than that necessary to carry out the atmospheric exposure test (some weeks instead of many years). Nevertheless the results provided by the salt spray test are only qualitative and their extrapolability to the real behaviour of the paint system's film‐metallic substrate is very difficult. Moreover, in some cases there is a discrepancy between the results of the salt spray test and the reality; for instance, it was observed some time ago that hot‐dip galvanized steel constitutes a better substrate for paints than bare steel, whereas the salt spray test results indicate the contrary. The present work represents only a part of a more conspicuous set of observations devoted to a comparison of laboratory and field results. In this first stage we examined, by means of salt spray and total immersion tests, the behaviour of bare steel and hot‐dip galvanized steel substrates, both phosphatized and coated by the same paint. The aim of this work was to ascertain if the results of the two methods are in accordance and, moreover, to compare the qualitative information given by the salt spray tests with those, quantitative, obtained by the electrode impedance technique on specimens immersed in 3% NaCl solution. By means of this technique it is possible to determine at the same time the values of the paint film resistance, of its capacitance, of the polarisation resistance and of the double layer pseudocapacitance related to the corrosion taking place on the metallic substrate and to ascertain the eventual intervention of diffusive phenomena into the corrosive process. Finally, this electrochemical method, because its non‐destructive nature, permits one to observe the variation of the values of overmentioned parameters as a function of time and therefore to interpret the evolution of the corrosion process.

Details

Anti-Corrosion Methods and Materials, vol. 38 no. 6
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 25 July 2019

Chi Zhang, Dajiang Zheng, Guang-Ling Song, Yang Guo, Ming Liu and Hamid Kia

This study aims to propose a simple experimental method to distinguish the galvanic corrosion, crevice corrosion and self-corrosion in metal/carbon fiber reinforced polymer (CFRP…

Abstract

Purpose

This study aims to propose a simple experimental method to distinguish the galvanic corrosion, crevice corrosion and self-corrosion in metal/carbon fiber reinforced polymer (CFRP) joints.

Design/methodology/approach

The corrosion behaviors of four different galvanic couples, whose anodes were Zn-coated DP590 steel and Al 6022, and cathodes were two kinds of CFRP, were investigated in immersion and GMW14872 cyclic conditions.

Findings

The results showed that the galvanic corrosion caused by direct contact between CFRP and metals was more serious than that caused by the jointing bolts. The corrosion damage caused by crevice corrosion was severer than that caused by galvanic corrosion. Self-corrosion was also significant, particularly under the cyclic salt spray condition.

Practical implications

Cyclic salt spray test may more reliably simulate the galvanic corrosion of a joint in industrial service environments, and real corrosion damage may be underestimated by a galvanic current measurement.

Originality/value

A deeper understanding of different corrosion mechanisms involved in CFRP/metal joints under different service conditions in industry has been given.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 June 1999

K.R. Baldwin and C.J.E. Smith

Examines accelerated methods for the corrosion testing of materials, coatings and surface treatments used in the aerospace and defence industries. The drawbacks with some current…

1695

Abstract

Examines accelerated methods for the corrosion testing of materials, coatings and surface treatments used in the aerospace and defence industries. The drawbacks with some current accelerated corrosion tests are examined, particularly the problems experienced with neutral salt spray tests. Specific examples are given which identify the acute discrepancy between salt spray and marine exposure in the corrosion testing of metallic coatings on steels. Examines some recent advances in corrosion testing of aerospace materials, pre‐treatments and organic coatings, and outlines some preliminary research conducted at DERA Farnborough in developing more accurate test methods.

Details

Aircraft Engineering and Aerospace Technology, vol. 71 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 8 November 2011

Svetlana Butylina, Ossi Martikka and Timo Kärki

The purpose of this paper is to study the effects of water immersion‐freeze‐thaw treatment on the physical properties, flexural strength (FS) and morphology of wood‐polypropylene…

Abstract

Purpose

The purpose of this paper is to study the effects of water immersion‐freeze‐thaw treatment on the physical properties, flexural strength (FS) and morphology of wood‐polypropylene composites containing pigments.

Design/methodology/approach

Wood‐polypropylene composites containing brown, green and grey pigments were compounded in a conical twin‐screw extruder. A composite manufactured without any pigment addition was used as a reference. The amount of pelletized wood, polypropylene and coupling agent (MAPP) was kept constant. The moisture content, thickness swelling (TS), FS and surface colour of the composites were measured before and after water immersion‐freeze‐thaw cycling. Scanning electron microscopy (SEM) was used to study the morphology of the composites.

Findings

FS and dimensional stability were reduced after exposure to water immersion‐freeze‐thaw cycling for all composites. The surface properties (colour and roughness) of the composites also changed after exposure to water immersion‐freeze‐thaw cycling. The degree of change depended on the presence of pigment and the type of polypropylene (neat or recycled), however.

Research limitations/implications

This study is a part of an ongoing study on weathering of wood‐polymer composites (WPC) containing different additives. The results of this study were obtained from accelerated laboratory experiments.

Practical implications

Inorganic pigments are widely used as additives in plastics, because they have an excellent UV absorption, good IR‐reflective properties and heat stability. The research revealed that metal‐containing pigments had an effect on degradation in quality of wood‐polypropylene composites exposed to water immersion‐freeze‐thaw cyclic treatment. The addition of metal‐containing pigments to composite formulation resulted in a higher susceptibility of wood‐polypropylene composites to water absorption, and as a consequence to a higher drop of FS compared to composites made without pigment. The polymer matrix plays an important role in the protection of WPC against weathering.

Originality/value

This paper will help in understanding possible problems in the durability of wood‐polypropylene composites compounded with metal‐based pigments when they are exposed to water immersion‐freeze‐thaw cyclic treatment.

Article
Publication date: 27 November 2020

Haoyue Zhang, Luqi Chang, Hongwei Zhang, Junyan Li, Zijiang Yang, Bingxuan Qiao, Zhenjiang Zhao, Chaofang Dong and Kai Zhang

The purpose of this paper is to study the mechanical and corrosion behaviors of selective laser melting (SLM) 30CrMnSiA steel.

Abstract

Purpose

The purpose of this paper is to study the mechanical and corrosion behaviors of selective laser melting (SLM) 30CrMnSiA steel.

Design/methodology/approach

The microstructure, mechanical behavior and corrosion resistance of SLM 30CrMnSiA steel were studied by electrochemical test and immersion experiment.

Findings

The results showed that the microstructure of SLM 30CrMnSiA steel contained equiaxed fine (25.0 µm) ferrite and lamellar pearlite. The tensile strength of SLM 30CrMnSiA steel under the process parameters is 1,447 MPa and the elongation is 7.5%. As the immersion/salt spray test time increased to 15 days/48 h, corrosion mainly occurred in the local position of the sample and corrosion resistance decreased. When the immersion/salt spray test time increased to 30 days/168 h, the corrosion production covered the surface of the samples and the corrosion resistance increased.

Originality/value

The paper can guide the application and in situ repair for low-alloy steel by additive manufacturing.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 September 1976

A. Marchese, A. Papo and G. Torriano

Summary Chlorinated rubber primers formulated with active pigments, which are claimed to be non‐toxic and non‐polluting, are investigated; they are designed for the protection of…

Abstract

Summary Chlorinated rubber primers formulated with active pigments, which are claimed to be non‐toxic and non‐polluting, are investigated; they are designed for the protection of ships (above the waterline), port installation, industrial plants, bridges, etc.

Details

Anti-Corrosion Methods and Materials, vol. 23 no. 9
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 23 May 2008

Frederico Guilherme Dantas dos Santos, Carlos Roberto Araújo and Vanessa de Freitas Cunha Lins

The purpose of this paper is to study the corrosion of the coupling of two different types of stainless steel, austenitic and ferritic, used in the fabrication of water reservoirs…

1403

Abstract

Purpose

The purpose of this paper is to study the corrosion of the coupling of two different types of stainless steel, austenitic and ferritic, used in the fabrication of water reservoirs in the solar energy industry.

Design/methodology/approach

Potentiodynamic polarization and gravimetric immersion tests were used to evaluate corrosion of the coupling of two different types of stainless steel, austenitic and ferritic.

Findings

The galvanic corrosion was not significant in the case of the coupling of AISI 304 and 444 steels. The difference of the open circuit potentials obtained for the AISI 304 and AISI 444 steels was 28 mV for the polished samples. The galvanic current density (ig) was 55 nA/cm2. The corrosion observed in the stainless steel couple was in the weld area.

Research limitations/implications

The methodology used is adequate to evaluate generalized galvanic corrosion. The problem of the corrosion in the coupling of the stainless steels is a problem of localized corrosion and the observed 28 mV potential difference was lower than the dispersion of results usually obtained from readings of corrosion potentials in electrochemical cells.

Practical implications

The use of two different types of steel in contact with each other may lead to galvanic corrosion, and the welding of steel pieces may lead to several corrosion problems. Since the boiler may be used in different countries, subject to a great diversity of water quality, corrosion may be a significant problem.

Originality/value

Literature data of the AISI 444 steel corrosion behaviour are still scarce. The coupling of two different stainless steels (AISI 304 and 444) in the water reservoir manufacturing was a necessary requirement of the solar energy industry. The manufacturers of boilers must evaluate and quantify the corrosion processes, which occur in the equipment used in the solar energy industry. As the solar energy industry has matured in the last ten years, the corrosion of this equipment may be a significant problem in due course.

Details

Anti-Corrosion Methods and Materials, vol. 55 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 6 June 2023

Xuehui Hao, Changzheng Wang, Shuai Guo, Jie Ma, Hui Chen and Xingchuan Zhao

The poor corrosion resistance of the ferrite-pearlite steel limits its application in marine engineering because of the enhanced galvanic effect caused by continuously accumulated…

Abstract

Purpose

The poor corrosion resistance of the ferrite-pearlite steel limits its application in marine engineering because of the enhanced galvanic effect caused by continuously accumulated cementite. Cr as one principal alloying element is commonly used to improve the corrosion resistance of steels. This paper aims to study the effect of Cr on corrosion behaviors of ferrite-pearlite steels in an acidic environment.

Design/methodology/approach

The tested steels were immersed in a simulated solution of 10 Wt.% NaCl with pH 0.85 for 72 h to evaluate the corrosion rate. After the immersion test, the corrosion morphologies and products were tested by scanning electron microscopy, energy dispersive X-ray analysis and X-ray diffraction. Meanwhile, an electrochemical workstation was used to study the electrochemical behaviors of samples.

Findings

At the initial corrosion stage, the corrosion rate increased in the sequence of Cr0, Cr0.5 and Cr1 steels, which was because of the competitive effect between the area ratio and the driving force caused by alloyed Cr. However, Cr1 steel exhibited the best corrosion resistance after a 72-h immersion test. This was because the alloyed Cr promoted the formation of protective Fe2O3 and FeCr2O4, which suppressed the preferential dissolution of ferrite and, thus, reduced the accumulation rate of carbides, resulting in the weakened galvanic corrosion.

Originality/value

This paper reports the role that Cr plays in the galvanic corrosion of ferrite-pearlite steels, which is important for the engineering application of ferrite-pearlite steels in marine environment.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

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