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Article
Publication date: 10 September 2021

Zhong Wu, Qing Hu, Zhenbo Qin, Yiwen Zhang, Da-Hai Xia and Wenbin Hu

Nickel-aluminum bronze (NAB) has been widely used in ship propellers. It is always subjected to local micro-plastic deformation in service environments. This paper aims to…

Abstract

Purpose

Nickel-aluminum bronze (NAB) has been widely used in ship propellers. It is always subjected to local micro-plastic deformation in service environments. This paper aims to study the influence of plastic deformation on the mechanical strength and corrosion resistance of NAB in 3.5 Wt.% NaCl solution.

Design/methodology/approach

Scanning electron microscope and X-ray diffraction were used to analyze the microstructure of NAB alloy with different plastic deformations. Mechanical properties of the sample were measured by tensile experiment, and corrosion behavior was studied by electrochemical measurements and the long-term immersion corrosion test.

Findings

Results showed that the plastic deformation caused lattice distortion but did not change the microstructure of NAB alloy. Microhardness and yield strength of NAB were significantly improved with the increase of deformation. The lattice distortion accelerated the formation of corrosion product film, which made the deformed alloy show a more positive open-circuit potential and an increased Rp. However, during the long-term immersion corrosion, the corrosion resistance of NAB alloys deteriorated with the increase of plastic deformation. This is because larger plastic deformation brought about higher internal stress in corrosion product film, which resulted in the premature peeling of the film and the loss of its protective effect on the alloy substrate.

Originality/value

Tensile plastic deformations were found to cause a decline in the corrosion resistance of NAB. And the mechanism was clarified from the evolution of corrosion products during the corrosion process.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 7 June 2021

Shixiong Wu, Zhiming Gao, Da-Hai Xia, Meijun Wu, Yingjie Liu and Wenbin Hu

This paper aims to study the effect of temperature on the process and kinetic parameters of the hydrogen evolution reaction of X80 under cathodic protection (CP) in 3.5…

Abstract

Purpose

This paper aims to study the effect of temperature on the process and kinetic parameters of the hydrogen evolution reaction of X80 under cathodic protection (CP) in 3.5% NaCl solution.

Design/methodology/approach

Potentiodynamic polarization combined with the hydrogen permeation test is used to analyze the hydrogen evolution reaction (HER) process and the rate-determining step for which is diagnosed through the electrochemical impedance spectrum method. Then, the influence of temperature on kinetic parameters of HER can be known from the results obtained by using the Iver-Pickering-Zamenzadeh model for data analysis.

Findings

The results show that the HER proceeds through Volmer–Tafel route with the Volmer reaction acting as the rate-controlling step; Increasing temperature gives a higher activity of the HER on X80, it also accelerates the hydrogen desorption and diffusion of hydrogen into the metal.

Originality/value

There exist few studies on the topic of how temperature affects the HER process. It is imperative to conduct a relevant study to give some instruction in cathodic protection system design and this paper fulfills this need.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 4 September 2020

Jian Song, Zhiming Gao, Chenxi Liu and Wenbin Hu

This paper aims to study the effect of flow rate (0.42∼2.09 m/s) on the corrosion behavior of WB36CN1 steel pipe in the simulated secondary circuit water environment…

Abstract

Purpose

This paper aims to study the effect of flow rate (0.42∼2.09 m/s) on the corrosion behavior of WB36CN1 steel pipe in the simulated secondary circuit water environment (170°C, 6 mg/L ethanolamine + 100 µg/L NaCl), for which an autoclave was used to simulate the secondary circuit environment for carrying out related experiments.

Design/methodology/approach

The corrosion behaviors were studied by electrochemical methods, morphological observations and elemental analysis.

Findings

As flow rate increases, the amplitude of the current noise fluctuates increased, noise resistance Rn and spectral noise resistance Rsn decreased, the shear stress on the surface of WB36CN1 steel increases, the oxygen content on the surface decreases, the roughness becomes smaller. Meanwhile, the energy of energy distribution plot is concentrated at high frequencies under the three flow conditions, the slopes of current power spectral density curve approach 0 db/decade. This means that the oxide on the surface becomes less and corrosion rate increases with increasing flow rate. The corrosion type of WB36CN1 steel was uniform corrosion; the degree of uniform corrosion is higher at high flow rate.

Originality/value

The effect of flow rate on the corrosion behavior of WB36CN1 steel pipe in the secondary circuit water environment was studied by using electrochemical methods in the laboratory. The effect mechanism of flow rate for corrosion behavior was obtained.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 6 March 2017

Ru Zhao, Da-Hai Xia, Shi-Zhe Song and Wenbin Hu

This paper aims to investigate the stress corrosion cracking (SCC) process of sensitized 304 stainless steel during the slow strain rate test by using the electrochemical…

Abstract

Purpose

This paper aims to investigate the stress corrosion cracking (SCC) process of sensitized 304 stainless steel during the slow strain rate test by using the electrochemical noise (EN) technique.

Design/methodology/approach

EN data are interpreted based on chaos and wavelet analyses, and correlation dimension and wavelet energy distribution are used as indicators for SCC process identification.

Findings

Experimental results reveal that the corrosion potential abruptly decreases from 180 to 100 mV at 6,300 s and the current increases from 10 to 100 nA accordingly, which is attributed to passive film breakdown and crack initiation. Chaos and wavelet analyses results reveal that, as crack initiates, the correlation dimensions increase from 1.2 to 1.9, and the corresponding distribution frequencies of maximum relative wavelet energy change from high frequency to low frequency.

Originality/value

SCC is monitored in lab, and crack initiation and propagation are identified by chaos and wavelet analyses. This work lays the foundation for SCC detection in field using EN.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 7 April 2020

Jun Hu, Wenbin Long, Xianzhong Song and Taijie Tang

Due to environmental externalities, micro-enterprises with profit-seeking features do not develop sufficient motivation for environmental governance. In a fiscally…

Abstract

Purpose

Due to environmental externalities, micro-enterprises with profit-seeking features do not develop sufficient motivation for environmental governance. In a fiscally decentralized system, local environmental protection authorities perform environmental supervision, and the intensity of the regulations that they implement has an important influence on corporate environmental governance. Based on the promotion tournament framework, this paper aims to discuss the driving mechanism of corporate environmental governance using turnover of environmental protection department directors (EPDDs) as an indicator.

Design/methodology/approach

Using samples of A-share companies listed on the Shanghai and Shenzhen exchanges from 2007 to 2014, this paper examines the impact of EPDD turnover on corporate environmental governance and its underlying mechanism.

Findings

The results show that corporate environmental governance exhibits a political periodicity that changes with the turnover of the EPDD, and the periodicity remains after controlling for the influence of changes in provincial party secretary and governor. Internal mechanisms analysis indicates that, without financial independence, local environmental protection departments rely on increasing sewage charges, not environmental protection subsidies, to promote corporate environmental governance. Further, considering heterogeneity among officials, it finds that the younger a new EPDD is, the more pronounced the periodicity of corporate environmental governance. However, there is no significant difference between in-system and out-system turnover.

Originality/value

In general, this paper describes the mechanisms of corporate environmental governance from the perspective of political economics, and the results have implications for the potential improvement of the government’s environmental supervision functions and the development of ecological civilization in China.

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Article
Publication date: 7 December 2021

Shijie Dai, Yufeng Zhao, Wenbin Ji, Jiaheng Mu and Fengbao Hu

This paper aims to present a control method to realize the constant force grinding of automobile wheel hub.

Abstract

Purpose

This paper aims to present a control method to realize the constant force grinding of automobile wheel hub.

Design/methodology/approach

A constant force control strategy combined by extended state observer (ESO) and backstepping control is proposed. ESO is used to estimate the total disturbance to improve the anti-interference and stability of the system and Backstepping control is used to improve the response speed of the system.

Findings

The simulation and grinding experimental results show that, compared with the proportional integral differential control and active disturbance rejection control, the designed controller can improve the dynamic response performance and anti-interference ability of the system and can quickly track the expected force and improve the grinding quality of the hub surface.

Originality/value

The main contribution of this paper lies in the proposed of a new constant force control strategy, which significantly improved the stability and precision of grinding force.

Details

Industrial Robot: the international journal of robotics research and application, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 13 September 2021

Jun Hu, Wenbin Long, Yu Wang and Linzi Zhou

Using a sample of listed Chinese companies that issued bonds from 2010 to 2019, the authors empirically test the link between CSR and corporate bond pricing, and the…

Abstract

Purpose

Using a sample of listed Chinese companies that issued bonds from 2010 to 2019, the authors empirically test the link between CSR and corporate bond pricing, and the mechanism and channels behind this link.

Design/methodology/approach

This study systematically examines whether and how corporate social responsibility (CSR) affects the corporate bond market in China.

Findings

Firms with better CSR have higher corporate bond credit ratings and lower corporate bond yield spreads. These associations remain stable in robustness checks, including checks that use regional typhoon disaster as an instrumental variable. The effects of CSR are more significant for firms with a worse information environment and for those operating in high-risk environments. Better CSR is associated with less earnings management, fewer financial restatements and less analyst forecast divergence. In addition, the effects of CSR are more pronounced after the 2013 market-oriented reform and when issuers are non-state-owned enterprises.

Practical implications

Because market participants can incorporate firms' CSR into their decision-making, establishing an effective channel for communicating CSR between issuers and market participants will enhance the effects of CSR.

Social implications

Researchers need to attend to the mechanisms behind the link between CSR and corporate bond pricing, and to the characteristics of strong environmental contingency in emerging markets, specifically the periods and scenarios in which the effects of CSR change.

Originality/value

This study provides systemic evidence that CSR benefits corporate bond pricing through both informational and reputational channels and that the effects of CSR vary by time and firm. These findings enrich the literatures on both the economic consequences of CSR and the determinants of corporate bond pricing, and provide a plausible explanation for mixed findings on the effects of CSR in previous studies.

Details

International Journal of Emerging Markets, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1746-8809

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Article
Publication date: 21 February 2020

Changsheng Wang, Xiao Han, Caixia Yang, Xiangkui Zhang and Wenbin Hou

Numerous finite elements are proposed based on analytical solutions. However, it is difficult to find the solutions for complicated governing equations. This paper aims to…

Abstract

Purpose

Numerous finite elements are proposed based on analytical solutions. However, it is difficult to find the solutions for complicated governing equations. This paper aims to present a novel formulation in the framework of assumed stress quasi-conforming method for the static and free vibration analysis of anisotropic and symmetric laminated plates.

Design/methodology/approach

Firstly, an initial stress approximation ruled by 17 parameters, which satisfies the equilibrium equations is derived to improve the performance of the constructed element. Then the stress matrix is treated as the weighted function to weaken the strain-displacement equations. Finally, the Timoshenko’s laminated composite beam functions are adopted as boundary string-net functions for strain integration.

Findings

Several numerical examples are presented to show the performance of the new element, and the results obtained are compared with other available ones. Numerical results have proved that the new element is free from shear locking and possesses high accuracy for the analysis of anisotropic and symmetric laminated plates.

Originality/value

This paper proposes a new QC element for the static and free vibration analysis of anisotropic and symmetric laminated plates. In contrast with the complicated analytical solutions of the equilibrium equations, an initial stress approximation ruled by 17 parameters is adopted here. The Timoshenkos laminated composite beam functions are introduced as boundary string-net functions for strain integration. Numerical results demonstrate the new element is free from shear locking and possesses high accuracy for the analysis of anisotropic and symmetric laminated plates.

Details

Engineering Computations, vol. 37 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 27 January 2012

Yuhong Wang, Jiangrong Tang and Wenbin Cao

The purpose of this paper is to make an evaluation and early warning prediction using grey prediction models and the index of process ability.

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Abstract

Purpose

The purpose of this paper is to make an evaluation and early warning prediction using grey prediction models and the index of process ability.

Design/methodology/approach

An early warning prediction for food security risk is proposed in this paper. A quality index is constructed and an improved grey prediction model is also presented. The quality index model is applied to measure the level of food quality; then the grey prediction model is applied to predict the trend of quality index for food in the future. A comparison between the predicted trends and standard limit proposed by experts is made to judge the food security risk.

Findings

The results in this paper indicate that more attention should be paid to the food security situation and steps should also should be taken to prevent harm to people's health from food.

Practical implications

The method presented in the paper could be used to make predictions for those systems which have the characteristic of small sample and poor information. The combination of grey prediction model and process ability index could also be applied to evaluation and early warning for those systems.

Originality/value

Food quality index is constructed for evaluating food security and an improved grey prediction model is also presented in this paper. The combination of these two models could be applied to make evaluation and warning prediction for food security risk with poor information.

Details

Grey Systems: Theory and Application, vol. 2 no. 1
Type: Research Article
ISSN: 2043-9377

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Article
Publication date: 2 October 2009

Weigang Cui, Xin Wang, Wenbin Li and Weilin Xu

The purpose of this paper is to present a dynamic analysis on the thermal and electrical properties of fabrics under wet conditions.

Abstract

Purpose

The purpose of this paper is to present a dynamic analysis on the thermal and electrical properties of fabrics under wet conditions.

Design/methodology/approach

A purpose‐built apparatus is applied to test the thermal and electrical properties of textiles in moisture absorption and liberation process. Relation between temperature and resistance of a cotton/polyester double‐layer fabric is also analysed.

Findings

The surface temperature of textiles shows three different stages in the process. The electrical resistance is linearly related to the reciprocal of the moisture regain of fabrics. In the moisture absorption and liberation process, surface temperature of cotton layer is higher than that of polyester layer. And the electrical resistance of cotton layer decreases more quickly than that of polyester layer. The electrical resistance changes earlier than surface temperature in the moisture‐liberation process.

Practical implications

The paper is helpful in not only the designing of sportswear, but also the devising of moisture‐testing apparatus.

Originality/value

A dynamic testing method is applied to characterize the thermal and electrical properties of textiles.

Details

International Journal of Clothing Science and Technology, vol. 21 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

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