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Abstract

Details

Heavy Metal Youth Identities: Researching the Musical Empowerment of Youth Transitions and Psychosocial Wellbeing
Type: Book
ISBN: 978-1-78756-849-5

Open Access
Article
Publication date: 29 February 2024

Guanchen Liu, Dongdong Xu, Zifu Shen, Hongjie Xu and Liang Ding

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous…

Abstract

Purpose

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Design/methodology/approach

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

Findings

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

Originality/value

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2633-6596

Keywords

Article
Publication date: 1 February 2005

S.A. Mashi, S.A. Yaro and P.N. Eyong

Contamination of the environment by heavy metals is a phenomenon of global importance today. When present in high concentrations in the environment, heavy metals may enter the…

537

Abstract

Purpose

Contamination of the environment by heavy metals is a phenomenon of global importance today. When present in high concentrations in the environment, heavy metals may enter the food chain from soils and result in health hazards. Accumulation in street dust is one major way through which heavy metals may find their way into soils and subsequently living tissues of plants, animals and human beings. In this paper, the magnitude and sources of some heavy metals (Cu, Mn, Fe, Cd, Pb and Zn) in street dust samples in and around Gwagwalada, Nigeria, were assessed.

Design/methodology/approach

Street dust samples were collected from 12 sites with and without varying levels of human activities (blacksmithing, motor repair works, metal working and fabrication, vehicular traffic and residential development) in the area and analysed by atomic absorption spectrophotometry to determine the magnitude and sources of accumulation of the above heavy metals in street dust in the study area.

Findings

The mean concentrations were found to be 210, 79, 97, 3.9, 120 and 96 μg g−1 respectively, for Pb, Zn, Cu, Cd, Fe and Mn across the various sampling sites. Samples collected from sites with human activities were found to contain concentrations of the metals that are generally higher than those in background areas (without human activities). However, metal working and fabrication, and motor repair works were found to have a stronger influence on the accumulation of the metals in the dust samples than vehicular traffic.

Practical implications

The results indicate that, contrary to what is expected, based on the observations made in several areas by many researchers elsewhere, metal working and fabrication, and motor repair works have a stronger influence on the accumulation of the metals in the dust samples than vehicular traffic in the study area.

Originality/value

Provides information on heavy metal contamination of the environment in an area of Nigeria.

Details

Management of Environmental Quality: An International Journal, vol. 16 no. 1
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 23 March 2020

Guochao Zheng, Fuli Wang, Baiping Yan and Runting Cheng

The purpose of this study is to suppress the temperature rise of high voltage wall bushing metal plate.

Abstract

Purpose

The purpose of this study is to suppress the temperature rise of high voltage wall bushing metal plate.

Design/methodology/approach

First, the authors built a model of a traditional metal plate and got the magnetic field intensity distribution by FEA tools. Optimized according to the magnetic field intensity distribution, the authors slot the traditional metal plate and embed permanent magnets in the slot. Finally, the authors got the temperature distribution diagrams of the above three cases at different current levels by FEA tools.

Findings

Slotted metal plate is beneficial to suppress magnetic induction intensity, but the improvement of the magnetic induction intensity uniformity is not obvious. The method of embedding a permanent magnet in a slotted metal plate can optimize the magnitude and uniformity of the magnetic induction intensity in the metal plate. The larger the current passing through the metal plate, the better the temperature suppression effect of the slotted metal plate and the slotted metal plate embedded in the permanent magnet.

Originality/value

The effect of structural factors, slotting plate and setting permanent magnets on slots on the temperature of supporting plate is studied. The paper proposes two methods, slotting metal panels and embedding permanent magnet metal panels, to solve the problems of eddy current loss and high calorific value of the panel, which is of great significance to the safety of the grid equipment.

Details

Circuit World, vol. 46 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 June 1994

Hussein I. Abdel‐Shafy, Werner Hegemann and Andrea Teiner

Describes a study carried out to evaluate the accumulation of heavymetals by two different vascular aquatic plants in the artificialwetlands which were constructed for the…

632

Abstract

Describes a study carried out to evaluate the accumulation of heavy metals by two different vascular aquatic plants in the artificial wetlands which were constructed for the treatment of municipal wastewater in Berlin, Germany. The studied plants were Pharagmites australis and Schoenoplectus lacustris. The investigated metals were: Zn, Cr, Cu, Fe, Cd, Ni and Pb. The translocation of such metals in the plant roots, stems and leaves was also determined. The level of metals in the influent and effluent of the wastewater, as well as the sludge, was investigated. The concentration factor of each metal by plants and sludge was further studied. Results revealed that P. australis has a higher tendency for the accumulation of metals than S. Lacustris. The level of metals was higher in roots, followed by leaves, then stems. Metals were more concentrated in the sludge than in the plants. Further study showed that the levels of metals in plants grown in the artificial wetlands were higher than in those grown in a “controlled” area. Concludes that vascular plants can act as scavengers of metals from the municipal wastewater while still maintaining a healthy status.

Details

Environmental Management and Health, vol. 5 no. 2
Type: Research Article
ISSN: 0956-6163

Keywords

Article
Publication date: 1 December 2005

N.M. Abd El‐Moniem, M.R. El‐Sourougy and D.A.F. Shaaban

Preparation of chelating resin to be used in the removal of heavy metal ions from solutions.

1018

Abstract

Purpose

Preparation of chelating resin to be used in the removal of heavy metal ions from solutions.

Design/methodology/approach

Chelating resin based on poly (glycidyl‐methacrylate‐co‐N, N‐methylene‐bis‐acrylamide) containing ethylenediamine was synthesised and used in removal of heavy metals from solutions.

Findings

The optimal pH values for adsorption of different metal ions occur in the range 4.0‐10.0 depending on the metal ion used. The adsorption of metal ions increases with increasing treatment duration to reach to the equilibrium state. Also, the adsorption of metal ions depends on the degree of cross linking of the chelating resin, and a higher degree of cross linking results in a lower degree of metal ion adsorption. The chelating resin was highly effective for the collection of metal ions by batch and column methods. The metal ions adsorbed could be eluted with 2M HNO3 except Co2+ and the resin could be reused.

Research limitations/implications

The different factors affecting the metal ions (Cu2+, Co2+, Cd2+, Zn2+, Pb2+ and Hg2+) loading in resin such as pH, contact time and cross linking density were studied.

Practical implications

The practical applicability of the chelating resin for final stage of waste water treatment is recommended for use as a polishing agent.

Originality/value

The resins prepared were used successfully in removing heavy metals from water.

Details

Pigment & Resin Technology, vol. 34 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 February 1980

William Sharpe

Introduction Clad metals are composites of two or more metals which are joined in a continuous manner by a metallurgical bond. The composite provides the specific advantages of…

Abstract

Introduction Clad metals are composites of two or more metals which are joined in a continuous manner by a metallurgical bond. The composite provides the specific advantages of both metals, usually the good corrosion resistance of the cladding metal and the strength and economy of the backing metal.

Details

Anti-Corrosion Methods and Materials, vol. 27 no. 2
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 28 October 2014

Rihan Omar Rihan

This paper aims to report an experimental investigation of the galvanic corrosion that occurs between the base metal and the welds in X52 carbon steel petroleum pipelines when…

Abstract

Purpose

This paper aims to report an experimental investigation of the galvanic corrosion that occurs between the base metal and the welds in X52 carbon steel petroleum pipelines when exposed in carbon dioxide (CO2)-containing saltwater at pH 4 at room temperature. The pipeline was fabricated by electric resistance welding (ERW).

Design/methodology/approach

The experimental setup was a closed glass cell equipped with a silver/silver chloride (Ag/AgCl) reference electrode, two working electrodes (the weld metal and the parent steel specimens) and a gas bubbler. The corrosion potential and polarization resistance of the base metal and the weld were determined using electrochemical testing methods: potentiodynamic polarization scans and linear polarization resistance measurement. The galvanic currents of the base metal when coupled to the weld metal were measured using zero resistance ammetry.

Findings

The weld metal was the anode of the couple for a very short time at the beginning of the experiment and then became the cathode until the end of the experiment. This indicates that electric resistance welded X52 steel pipe is a promising material to be operated in CO2-containing saltwater at pH 4 and 25°C because the weld area is cathodic to the parent metal, the value of the galvanic current is very low (in the order of nanoamps) and the area of the anode (i.e. the parent metal) is significantly larger than that of the cathode (weld metal).

Research limitations/implications

Further experimental research could be performed to investigate the galvanic corrosion behavior between the parent metal and the weld area of X52 carbon steel petroleum pipelines in CO2-containing saltwater at different pH values, temperature and velocity.

Practical implications

Electric resistance welded X52 steel pipe is a promising material for use with CO2-containing saltwater environments at pH 4 and 25°C.

Originality/value

The new information presented in the paper is the galvanic corrosion behavior between the parent metal and the ERW weld metal of X52 carbon steel in CO2-containing solutions. The paper should be useful to researchers working in the field of oil industry corrosion.

Details

Anti-Corrosion Methods and Materials, vol. 61 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 January 1972

Every metal has a range of environmental conditions against which it is resistant or sufficiently resistant as to make the metal economically feasible. Unfortunately it is almost…

Abstract

Every metal has a range of environmental conditions against which it is resistant or sufficiently resistant as to make the metal economically feasible. Unfortunately it is almost a rule of thumb that the more expensive the metal the smaller the range. In most cases the resistance of the metal is a function of the metal thickness, but the function is such that relatively thin metals can produce very long lives.

Details

Anti-Corrosion Methods and Materials, vol. 19 no. 1
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 8 February 2024

Akhil Khajuria, Anurag Misra and S. Shiva

An experimental investigation for developing structure-property correlations of hot-rolled E410 steels with different carbon contents, i.e. 0.04wt.%C and 0.17wt.%C metal active…

Abstract

Purpose

An experimental investigation for developing structure-property correlations of hot-rolled E410 steels with different carbon contents, i.e. 0.04wt.%C and 0.17wt.%C metal active gas (MAG) and cold metal transfer (CMT)-MAG weldments was undertaken.

Design/methodology/approach

Mechanical properties and microstructure of MAG and CMT-MAG weldments of two E410 steels with varying content of carbon were compared using standardized mechanical testing procedures, and conventional microscopy.

Findings

0.04wt.%C steel had strained ferritic and cementite sub-structures in blocky shape and large dislocation density, while 0.17wt.%C steel consisted of pearlite and polygonal ductile ferrite. This effected yield strength (YS), and microhardness being larger in 0.04wt.%C steel, %elongation being larger in 0.17wt.%C steel. Weldments of both E410 steels obtained with CMT-MAG performed better than MAG in terms of YS, ultimate tensile strength (UTS), %elongation, and toughness. It was due to low heat input of CMT-MAG that resulted in refinement of weld metal, and subzones of heat affected zone (HAZ).

Originality/value

A substantial improvement in YS (∼9%), %elongation (∼38%), and room temperature impact toughness (∼29%) of 0.04wt.%C E410 steel is achieved with CMT-MAG over MAG welding. Almost ∼10, ∼12.5, and ∼16% increment in YS, %elongation, and toughness of 0.17wt.%C E410 steel is observed with CMT-MAG. Relatively low heat input of CMT-MAG leads to development of fine Widmanstätten and acicular ferrite in weld metal and microstructural refinement in HAZ subzones with nearly similar characteristics of base metal.

Details

International Journal of Structural Integrity, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-9864

Keywords

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