Search results

1 – 10 of 23
Article
Publication date: 19 October 2023

Sara Pope and Robert L. Jackson

The purpose of this paper is to use a wear test to determine the effect of sand on the wear rates of materials typically used in aerospace applications. Once a repeatable wear…

Abstract

Purpose

The purpose of this paper is to use a wear test to determine the effect of sand on the wear rates of materials typically used in aerospace applications. Once a repeatable wear test has been established, it can be used to test any combination of materials or coatings. The effectiveness of several different test methods will also be evaluated, including the sample height, surface roughness and mass difference. In addition, the current work will observe the differences between applying sand before the samples are brought into contact or after. The wear rates obtained from these tests could also be used to predict the wear of other components in similar abrasive particulate environments.

Design/methodology/approach

A modified block-on-flat wear test of anodized aluminum on hard coat anodized aluminum was used to study this. The experiments were performed with and without sand to study the effects of the sand. Two methods of adding sand were also evaluated. Weighing and profilometry were used to study the differences between the tests.

Findings

Wear rates have been calculated based on both the change in the masses of the samples and the change in the height between the upper and lower samples over the course of each test. The wear rates from the change in the masses are repeatable with and without sand, but the results for the change in height show no repeatability without sand. In addition, only in the presence of sand do the trends for the two methods agree. The wear rate was found to be non-linear as a function of load and therefore not in agreement with Archard’s Wear Law. The wear rate also increased significantly when sand was present in the contact for the duration of the test. The sand appears to change the wear mechanism from an adhesive to an abrasive mechanism. Black wear particles formed both when there was sand and when there was not sand. The source of these particles has been investigated but not determined.

Originality/value

This work has not been previously published and is the original work of the authors.

Details

Industrial Lubrication and Tribology, vol. 75 no. 9
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 24 January 2024

Dexin Chen, Hongyuan He, Zhixin Kang and Wei Li

This study aims to review the current one-step electrodeposition of superhydrophobic coatings on metal surfaces.

Abstract

Purpose

This study aims to review the current one-step electrodeposition of superhydrophobic coatings on metal surfaces.

Design/methodology/approach

One-step electrodeposition is a versatile and simple technology to prepare superhydrophobic coatings on metal surfaces.

Findings

Preparing superhydrophobic coatings by one-step electrodeposition is an efficient method to protect metal surfaces.

Originality/value

Even though there are several technologies, one-step electrodeposition still plays a significant role in producing superhydrophobic coatings.

Details

Anti-Corrosion Methods and Materials, vol. 71 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 12 December 2023

Ziru Zhou, Songlin Zheng, Jiahuan Chen, Ting Zhang, Zhen He and Yuxin Wang

The high specific strength makes magnesium alloys have a wide range of applications in aerospace, military, automotive, marine and construction industries. However, its poor…

Abstract

Purpose

The high specific strength makes magnesium alloys have a wide range of applications in aerospace, military, automotive, marine and construction industries. However, its poor corrosion resistance and weldability have limited its development and application. Friction stir welding (FSW) can effectively avoid the defects of fusion welding. However, the microstructure, mechanical properties and corrosion behavior of FSW joints in magnesium alloys vary among different regions. The purpose of this paper is to review the corrosion of magnesium alloy FSW joints, and to summarize the protection technology of welded joints.

Design/methodology/approach

The corrosion of magnesium alloy FSW joints includes electrochemical corrosion and stress corrosion. This paper summarizes corrosion protection techniques for magnesium alloys FSW joints, focusing on composition, microstructure changes and surface treatment methods.

Findings

Currently, this research is mainly focused on enhancing the corrosion resistance of magnesium alloy FSW joints by changing compositions, structural modifications and surface coating technologies. Refinement of the grains can be achieved by adjusting welding process parameters, which in turn minimizes the effects of the second phase on the alloy’s corrosion resistance.

Originality/value

This paper presents a comprehensive review on the corrosion and protection of magnesium alloys FSW joints, covering the latest research advancements and practical applications. It aims to equip researchers with a better insight into the field and inspire new studies on this topic.

Details

Anti-Corrosion Methods and Materials, vol. 71 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 16 October 2023

Y.F. Shu, B. Jiang, C. Wang and R.G. Song

The purpose of this paper is to study the effects of voltage on microstructure and properties of micro-arc oxidation (MAO) ceramic coatings formed on AZ31B magnesium alloy under…

Abstract

Purpose

The purpose of this paper is to study the effects of voltage on microstructure and properties of micro-arc oxidation (MAO) ceramic coatings formed on AZ31B magnesium alloy under the constant current–constant voltage operation mode.

Design/methodology/approach

The wear and corrosion resistance of MAO coating on AZ31B magnesium alloy was studied by MAO in silicate electrolyte under constant current and constant voltage.

Findings

When the voltage is 360 V, the wear and corrosion resistance of AZ31B magnesium alloy is the best.

Originality/value

The wear and corrosion resistance of MAO coating on AZ31B magnesium alloy was studied by friction wear and electrochemical workstation.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 21 December 2023

Xinran Zhao, Yingying Pang, Gang Wang, Chenhui Xia, Yuan Yuan and Chengqian Wang

This paper aims to realize the vertical interconnection in 3D radio frequency (RF) circuit by coaxial transitions with broad working bandwidth and small signal loss.

Abstract

Purpose

This paper aims to realize the vertical interconnection in 3D radio frequency (RF) circuit by coaxial transitions with broad working bandwidth and small signal loss.

Design/methodology/approach

An advanced packaging method, 12-inch wafer-level through-mold-via (TMV) additive manufacturing, is used to fabricate a 3D resin-based coaxial transition with a continuous ground wall (named resin-coaxial transition). Designation and simulation are implemented to ensure the application universality and fabrication feasibility. The outer radius R of coaxial transition is optimized by designing and fabricating three samples.

Findings

The fabricated coaxial transition possesses an inner radius of 40 µm and a length of 200 µm. The optimized sample with an outer radius R of 155 µm exhibits S11 < –10 dB and S21 > –1.3 dB at 10–110 GHz and the smallest insertion loss (S21 = 0.83 dB at 77 GHz) among the samples. Moreover, the S21 of the samples increases at 58.4–90.1 GHz, indicating a broad and suitable working bandwidth.

Originality/value

The wafer-level TMV additive manufacturing method is applied to fabricate coaxial transitions for the first time. The fabricated resin-coaxial transitions show good performance up to the W-band. It may provide new strategies for novel designing and fabricating methods of RF transitions.

Details

Soldering & Surface Mount Technology, vol. 36 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 20 March 2024

Shufeng Tang, Yongsheng Kou, Guoqing Zhao, Huijie Zhang, Hong Chang, Xuewei Zhang and Yunhe Zou

The purpose of this paper is to design a climbing robot connected by a connecting rod mechanism to achieve multi-functional tasks such as obstacles crossing and climbing of power…

Abstract

Purpose

The purpose of this paper is to design a climbing robot connected by a connecting rod mechanism to achieve multi-functional tasks such as obstacles crossing and climbing of power transmission towers.

Design/methodology/approach

A connecting rod type gripper has been designed to achieve stable grasping of angle steel. Before grasping, use coordination between structures to achieve stable docking and grasping. By using the alternating movements of two claws and the middle climbing mechanism, the climbing and obstacle crossing of the angle steel were achieved.

Findings

Through a simple linkage mechanism, a climbing robot has been designed, greatly reducing the overall mass of the robot. It can also carry a load of 1 kg, and the climbing mechanism can perform stable climbing. The maximum step distance of the climbing robot is 543 mm, which can achieve the crossing of angle steel obstacles.

Originality/value

A transmission tower climbing mechanism was proposed by analyzing the working environment. Through the locking ability of the screw nut, stable clamping of the angle steel is achieved, and a pitch mechanism is designed to adjust the posture of the hand claw.

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

Keywords

Article
Publication date: 18 March 2024

Prosun Mandal, Srinjoy Chatterjee and Shankar Chakraborty

In many of today’s manufacturing industries, such as automobile, aerospace, defence, die and mould making, medical and electrical discharge machining (EDM) has emerged as an…

Abstract

Purpose

In many of today’s manufacturing industries, such as automobile, aerospace, defence, die and mould making, medical and electrical discharge machining (EDM) has emerged as an effective material removal process. In this process, a series of discontinuous electric discharges is used for removing material from the workpiece in the form of craters generating a replica of the tool into the workpiece in a dielectric environment. Appropriate selection of the tool electrode material and combination of input parameters is an important requirement for performance enhancement of an EDM process. This paper aims to optimize an EDM process using single-valued neutrosophic grey relational analysis using Cu-multi-walled carbon nanotube (Cu-MWCNT) composite tool electrode.

Design/methodology/approach

This paper proposes the application of grey relational analysis (GRA) in a single-valued neutrosophic fuzzy environment to identify the optimal parametric intermix of an EDM process while considering Cu-MWCNT composite as the tool electrode material. Based on Taguchi’s L9 orthogonal array, nine experiments are conducted at varying combinations of four EDM parameters, i.e. pulse-on time, duty factor, discharge current and gap voltage, with subsequent measurement of two responses, i.e. material removal rate (MRR) and tool wear rate (TWR). The electrodeposition process is used to fabricate the Cu-MWCNT composite tool.

Findings

It is noticed that both the responses would be simultaneously optimized at higher levels of pulse-on time (38 µs) and duty factor (8), moderate level of discharge current (5 A) and lower level of gap voltage (30 V). During bi-objective optimization (maximization of MRR and minimization of TWR) of the said EDM process, the achieved values of MRR and TWR are 243.74 mm3/min and 0.001034 g/min, respectively.

Originality/value

Keeping in mind the type of response under consideration, their measured values for each of the EDM experiments are expressed in terms of linguistic variables which are subsequently converted into single-valued neutrosophic numbers. Integration of GRA with single-valued neutrosophic sets would help in optimizing the said EDM process with the Cu-MWCNT composite tool while simultaneously considering truth-membership, indeterminacy membership and falsity-membership degrees in a human-centric uncertain decision-making environment.

Details

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

Keywords

Article
Publication date: 22 March 2024

Catarina Gonçalves Rodrigues and Bruno Barbosa Sousa

This research seeks to understand whether employer branding (EB) and internal marketing (IM) are fundamental to the challenge of attracting and retaining talent and how these…

Abstract

Purpose

This research seeks to understand whether employer branding (EB) and internal marketing (IM) are fundamental to the challenge of attracting and retaining talent and how these strategies can help companies to overcome the difficulties related to the talent shortage, from the perspective of a SME Portuguese metallurgical industry.

Design/methodology/approach

The research resorts to a case study of a qualitative nature, through a semi-structured interview with the head of the human resources (HR) training and development area of the Navarra Group, and quantitative, through surveys to its employees. Based on the literature, a conceptual model was constructed, whose application allowed us to perceive the relationships between the practices of EB and IM; satisfaction, motivation and commitment; attraction and retention.

Findings

The exploratory interview concluded that organizations consider EB and IM essential for an effective talent management strategy. The quantitative results demonstrate that IM and EB practices implemented in the organization contribute to the satisfaction, motivation and involvement of employees, which results in a decrease in the intention to leave. It is also noted that these practices promote an increase in the perception of organizational attractiveness, which represents a positive impact on its ability to attract.

Research limitations/implications

From a theoretical perspective, the research contributes to the development of knowledge about IM, EB and talent management, providing relevant data that can help define the best strategies for attraction and retention, from the point of view of IM and EB.

Originality/value

The research presents preliminary insights that can be an auxiliary tool for HR managers and professionals in the context of industrial SMEs.

Details

EuroMed Journal of Business, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1450-2194

Keywords

Article
Publication date: 3 November 2023

Dongdong Song, Wenxiang Qin, Qian Zhou, Dong Xu and Bo Zhang

The anticorrosion coatings used in marine and atmospheric environment are subjected to many environmental factors. And the aging failure has been puzzling researchers. The purpose…

Abstract

Purpose

The anticorrosion coatings used in marine and atmospheric environment are subjected to many environmental factors. And the aging failure has been puzzling researchers. The purpose of this study is to find the correlation between the initial aging of epoxy coatings and the typical marine atmospheric environmental factors.

Design/methodology/approach

The epoxy coatings were subjected to a one-year exposure in three typical marine atmospheres. Meanwhile, principal component analysis, linear regression and Spearman and gray correlation analysis were applied to quantify the environmental characteristics and establish correlations with the coating aging.

Findings

The results indicate that the coating will undergo macroscopic fading and chalking upon exposure to the marine atmosphere, while microscopic examination reveals holes, cracks and partial peeling. The adhesion performance and electrochemical properties of the coating deteriorated with prolonged exposure, coating aging mainly occurs with the generation of O-H bonds and the breakage of molecular chains such as C-N and C-O-C. The coating was most deeply aged after exposure to the Xisha, followed by Zhoushan and finally Qingdao. Environmental factors affect the photooxidative aging and hydrolytic degradation processes of coatings and thus coating aging. To further demonstrate the correlation between environmental factors and coating aging, principal component analysis was used. The correlation model between environmental factors and coating aging was subsequently obtained. The correlation model between the rate of coating adhesion loss (E) and the comprehensive evaluation parameter of environmental factors (Z) is expressed as E = 0.142 + 0.028Z. Meanwhile, the Spearman correlation analysis and gray correlation method were used to investigate the impact of each environmental factor on coating aging. Solar irradiation, relative humidity and wetting time have the highest correlation with coating aging, which are all above 0.8 and have the greatest influence on coating aging; wind speed and temperature have the smallest correlation with coating aging, which are about 0.6 and have the least influence on coating aging.

Originality/value

This paper establishes a correlation between typical marine environmental factors and coating aging performance, which is crucial for predicting the service life of other coatings in diverse environments.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 18 October 2022

Reza Amini and Pooneh Kardar

This paper aims to achieve phosphating via optimal features of Mg metal as a suitable base coating, which is considered for other properties such as barrier properties against the…

Abstract

Purpose

This paper aims to achieve phosphating via optimal features of Mg metal as a suitable base coating, which is considered for other properties such as barrier properties against the passage of several factors.

Design/methodology/approach

In this research, in the phosphate bath, immersion time, temperature and the content of sodium nitrite as an accelerator were changed.

Findings

As a result, increasing the immersion time of AZ31 Mg alloy samples in the phosphating bath as well as increasing the ratio of sodium dodecyl sulfate (SDS) concentration to sodium nitrite concentration in the phosphating bath formulation increase the mass of phosphating formed per unit area of the Mg alloy. The results of the scanning electron microscope test showed phosphating is not completely formed in short immersion times, which is a thin and uneven layer.

Research limitations/implications

Mg and its alloys are sensitive to galvanic corrosion, which would lead to generating several holes in the metal. As such, it causes a decrease in mechanical stability as well as an unfavorable appearance.

Practical implications

Mg is used in several industries such as automobile and computer parts, mobile phones, astronaut compounds, sports goods and home appliances.

Social implications

Nevertheless, Mg has high chemical reactivity, so an oxide-hydroxide layer is formed on its surface, which has a harmful effect on the adhesion and uniformity of the coating applied on Mg.

Originality/value

By increasing the ratio of SDS concentration to sodium nitrite concentration in the phosphating bath, the corrosion resistance of the phosphating increases.

Details

Pigment & Resin Technology, vol. 53 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of 23