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Article
Publication date: 20 December 2023

Fadwa M. Al Chamaa, Ahmad El Ghor and Elie Hantouche

This study aims at investigating the effect of bolt hole-making processes on the post-fire behavior of S235 steel plates.

Abstract

Purpose

This study aims at investigating the effect of bolt hole-making processes on the post-fire behavior of S235 steel plates.

Design/methodology/approach

A total of nine steel plates with a single bolt hole are tested. The single bolt holes are fabricated using three different hole-making processes: drilling, waterjet and plasma. Among the nine steel plates, three fabricated specimens are control specimens and are tested at ambient temperature. The six remaining steel plates with a single bolt hole are subjected to a complete heating-cooling cycle and then monotonically loaded until failure. The six fabricated specimens are first heated up to two different temperatures 800 and 925 °C, and then cooled back to the ambient prior to loading.

Findings

The results show that after being exposed to post-fire temperatures (800 and 925 °C), the maximum decrease in strength of the S235 steel plate was 6% (at 925 °C), 14% (at 925 °C) and 22% (at 800 °C) when compared to the results of ambient specimens for waterjet, drilled and plasma bolt holes, respectively. For post-fire temperature tests, drilled and waterjet bolt hole-making processes result in having approximately the same load-displacement response, and both have larger strength and ductility than those obtained using plasma cutting.

Originality/value

This study provides preliminary data to guide the steel designers and fabricators in choosing the most suitable hole-making process for fire applications and to quantify the post-fire reduction in capacity of S235 plates.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

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 2024

Suvranshu Pattanayak, Susanta Kumar Sahoo, Ananda Kumar Sahoo, Raviteja Vinjamuri and Pushpendra Kumar Dwivedi

This study aims to demonstrate a modified wire arc additive manufacturing (AM) named non-transferring arc and wire AM (NTA-WAM). Here, the build plate has no electrical arc…

Abstract

Purpose

This study aims to demonstrate a modified wire arc additive manufacturing (AM) named non-transferring arc and wire AM (NTA-WAM). Here, the build plate has no electrical arc attachment, and the system’s arc is ignited between tungsten electrode and filler wire.

Design/methodology/approach

The effect of various deposition conditions (welding voltage, travel speed and wire feed speed [WFS]) on bead characteristics is studied through response surface methodology (RSM). Under optimum deposition condition, a single-bead and thin-layered part is fabricated and subjected to microstructural, tensile testing and X-ray diffraction study. Moreover, bulk texture analysis has been carried out to illustrate the effect of thermal cycles and tensile-induced deformations on fibre texture evolutions.

Findings

RSM illustrates WFS as a crucial deposition parameter that suitably monitors bead width, height, penetration depth, dilution, contact angle and microhardness. The ferritic (acicular and polygonal) and lath bainitic microstructure is transformed into ferrite and pearlitic micrographs with increasing deposition layers. It is attributed to a reduced cooling rate with increased depositions. Mechanical testing exhibits high tensile strength and ductility, which is primarily due to compressive residual stress and lattice strain development. In deposits, ϒ-fibre evolution is more resilient due to the continuous recrystallisation process after each successive deposition. Tensile-induced deformation mostly favours ζ and ε-fibre development due to high strain accumulations.

Originality/value

This modified electrode arrangement in NTA-WAM suitably reduces spatter and bead height deviation. Low penetration depth and dilution denote a reduction in heat input that enhances the cooling rate.

Details

Rapid Prototyping Journal, vol. 30 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 11 January 2024

Qiang Sun, Quantong Jiang, Siwei Wu, Chang Liu, Heng Tang, L. Song, Hao Shi, Jizhou Duan and BaoRong Hou

The purpose of this paper is to explore the effect of ZnO on the structure and properties of micro-arc oxidation (MAO) coating on rare earth magnesium alloy under large…

Abstract

Purpose

The purpose of this paper is to explore the effect of ZnO on the structure and properties of micro-arc oxidation (MAO) coating on rare earth magnesium alloy under large concentration gradient.

Design/methodology/approach

The macroscopic and microscopic morphology, thickness, surface roughness, chemical composition and structure of the coating were characterized by different characterization methods. The corrosion resistance of the film was studied by electrochemical and scanning Kelvin probe force microscopy. The results show that the addition of ZnO can significantly improve the compactness and corrosion resistance of the MAO coating, but the high concentration of ZnO will cause microcracks, which will reduce the corrosion resistance to a certain extent.

Findings

When the concentration of zinc oxide is 8 g/L, the compactness and corrosion resistance of the coating are the best, and the thickness of the coating is positively correlated with the concentration of ZnO.

Research limitations/implications

Too high concentration of ZnO reduces the performance of MAO coating.

Practical implications

The MAO coating prepared by adding ZnO has good corrosion resistance. Combined with organic coatings, it can be applied in corrosive marine environments, such as ship parts and hulls. To a certain extent, it can reduce the economic loss caused by corrosion.

Originality/value

The effect of ZnO on the corrosion resistance of MAO coating in electrolyte solution was studied systematically, and the conclusion was new to the common knowledge.

Details

Anti-Corrosion Methods and Materials, vol. 71 no. 2
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: 3 October 2023

Zonglin Lei, Zunge Li and Yangyi Xiao

This study aims to investigate the surface modification on 20CrMnTi gear steel individually treated by diamond-like carbon films and nitride coatings.

Abstract

Purpose

This study aims to investigate the surface modification on 20CrMnTi gear steel individually treated by diamond-like carbon films and nitride coatings.

Design/methodology/approach

For this purpose, the mechanical properties of a-C:H, ta-C and AlCrSiN coatings are characterized by nano-indentation and scratch tests. The friction and wear behaviors of these three coatings are evaluated by ball-on-disc tribological experiments under dry contact conditions.

Findings

The results show that the a-C:H coating has the highest coating-substrate adhesion strength (495 mN) and the smoothest surface (Ra is about 0.045 µm) compared with the other two coatings. The AlCrSiN coating shows the highest mean coefficient of friction (COF), whereas the ta-C coating exhibits the lowest one (steady at about 0.16). The carbon-based coatings possess excellent self-lubricating properties compared with nitride ceramic ones, which effectively reduce the COF by about 64%. The major failure mode of carbon-based coatings in dry contact is slight abrasive wear. The damage of AlCrSiN coating is mainly adhesive wear and abrasive wear.

Originality/value

It is suggested that the carbon-based film can effectively improve the friction-reducing and wear resistance performance of the gear steel surface, which has a promising application prospect in the mechanical transmission field.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0129/

Details

Industrial Lubrication and Tribology, vol. 75 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 15 December 2023

Muhammad Arif Mahmood, Chioibasu Diana, Uzair Sajjad, Sabin Mihai, Ion Tiseanu and Andrei C. Popescu

Porosity is a commonly analyzed defect in the laser-based additive manufacturing processes owing to the enormous thermal gradient caused by repeated melting and solidification…

Abstract

Purpose

Porosity is a commonly analyzed defect in the laser-based additive manufacturing processes owing to the enormous thermal gradient caused by repeated melting and solidification. Currently, the porosity estimation is limited to powder bed fusion. The porosity estimation needs to be explored in the laser melting deposition (LMD) process, particularly analytical models that provide cost- and time-effective solutions compared to finite element analysis. For this purpose, this study aims to formulate two mathematical models for deposited layer dimensions and corresponding porosity in the LMD process.

Design/methodology/approach

In this study, analytical models have been proposed. Initially, deposited layer dimensions, including layer height, width and depth, were calculated based on the operating parameters. These outputs were introduced in the second model to estimate the part porosity. The models were validated with experimental data for Ti6Al4V depositions on Ti6Al4V substrate. A calibration curve (CC) was also developed for Ti6Al4V material and characterized using X-ray computed tomography. The models were also validated with the experimental results adopted from literature. The validated models were linked with the deep neural network (DNN) for its training and testing using a total of 6,703 computations with 1,500 iterations. Here, laser power, laser scanning speed and powder feeding rate were selected inputs, whereas porosity was set as an output.

Findings

The computations indicate that owing to the simultaneous inclusion of powder particulates, the powder elements use a substantial percentage of the laser beam energy for their melting, resulting in laser beam energy attenuation and reducing thermal value at the substrate. The primary operating parameters are directly correlated with the number of layers and total height in CC. Through X-ray computed tomography analyses, the number of layers showed a straightforward correlation with mean sphericity, while a converse relation was identified with the number, mean volume and mean diameter of pores. DNN and analytical models showed 2%–3% and 7%–9% mean absolute deviations, respectively, compared to the experimental results.

Originality/value

This research provides a unique solution for LMD porosity estimation by linking the developed analytical computational models with artificial neural networking. The presented framework predicts the porosity in the LMD-ed parts efficiently.

Article
Publication date: 31 July 2023

Shekhar Srivastava, Rajiv Kumar Garg, Anish Sachdeva, Vishal S. Sharma, Sehijpal Singh and Munish Kumar Gupta

Gas metal arc-based directed energy deposition (GMA-DED) process experiences residual stress (RS) developed due to heat accumulation during successive layer deposition as a…

Abstract

Purpose

Gas metal arc-based directed energy deposition (GMA-DED) process experiences residual stress (RS) developed due to heat accumulation during successive layer deposition as a significant challenge. To address that, monitoring of transient temperature distribution concerning time is a critical input. Finite element analysis (FEA) is considered a decisive engineering tool in quantifying temperature and RS in all manufacturing processes. However, computational time and prediction accuracy has always been a matter of concern for FEA-based prediction of responses in the GMA-DED process. Therefore, this study aims to investigate the effect of finite element mesh variations on the developed RS in the GMA-DED process.

Design/methodology/approach

The variation in the element shape functions, i.e. linear- and quadratic-interpolation elements, has been used to model a single-track 10-layered thin-walled component in Ansys parametric design language. Two cases have been proposed in this study: Case 1 has been meshed with the linear-interpolation elements and Case 2 has been meshed with the combination of linear- and quadratic-interpolation elements. Furthermore, the modelled responses are authenticated with the experimental results measured through the data acquisition system for temperature and RS.

Findings

A good agreement of temperature and RS profile has been observed between predicted and experimental values. Considering similar parameters, Case 1 produced an average error of 4.13%, whereas Case 2 produced an average error of 23.45% in temperature prediction. Besides, comparing the longitudinal stress in the transverse direction for Cases 1 and 2 produced an error of 8.282% and 12.796%, respectively.

Originality/value

To avoid the costly and time-taking experimental approach, the experts have suggested the utilization of numerical methods in the design optimization of engineering problems. The FEA approach, however, is a subtle tool, still, it faces high computational cost and low accuracy based on the choice of selected element technology. This research can serve as a basis for the choice of element technology which can predict better responses in the thermo-mechanical modelling of the GMA-DED process.

Details

Rapid Prototyping Journal, vol. 29 no. 10
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 6 September 2023

Donghui Hu, Shenyou Song, Zongxing Zhang and Linfeng Wang

This paper aims to figure out the conundrum that the corrosion resistance longevity of steel wires for bridge cables was arduous to meet the requirements.

Abstract

Purpose

This paper aims to figure out the conundrum that the corrosion resistance longevity of steel wires for bridge cables was arduous to meet the requirements.

Design/methodology/approach

The “two-step” hot-dip coating process for cable steel wires was developed, which involved first hot-dip galvanizing and then hot-dip galvanizing of aluminum magnesium alloy. The corrosion rate, polarization curve and impedance of Zn–6Al–1Mg and Zn–10Al–3Mg alloy-coated steel wires were compared through acetate spray test and electrochemical test, and the corrosion mechanism of Zn–Al–Mg alloy-coated steel wires was revealed.

Findings

The corrosion resistance of Zn–10Al–3Mg alloy-coated steel wires had the best corrosion resistance, which was more than seven times that of pure zinc-coated steel wires. The corrosion current of Zn–10Al–3Mg alloy-coated steel wires was lower than that of Zn–6Al–1Mg alloy-coated steel wires, whereas the capacitive arc and impedance value of the former were higher than that of the latter, making it clear that the corrosion resistance of Zn–10Al–3Mg was better than that of Zn–6Al–1Mg alloy coating. Moreover, the Zn–Al–Mg alloy-coated steel wires for bridge cables had the function of coating “self-repairing.”

Originality/value

Controlling the temperature and time of the hot dip galvanizing stage can reduce the thickness of transition layer and solve the problem of easy cracking of the transition layer in the Zn–Al–Mg alloy coating due to the Sandelin effect.

Details

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

Keywords

Article
Publication date: 13 December 2023

Ferhat Ceritbinmez, Yusuf Kanca, Ahmet Tuna and Erdoğan Kanca

FeNi36 (Invar-36) alloy is widely used in the fabrication of molding tools in aerospace industries but there remains a need to improve its wear and friction performance due to its…

Abstract

Purpose

FeNi36 (Invar-36) alloy is widely used in the fabrication of molding tools in aerospace industries but there remains a need to improve its wear and friction performance due to its relatively low hardness. The formation of a heat affected zone (HAZ) on the surface of Invar-36 cut by wire electric discharge machining (WEDM) is promising to enhance its tribological properties. This study aims to investigate the tribological performance of WEDM-treated Invar-36 via a ball-on-disk tribometer in dry-sliding conditions.

Design/methodology/approach

The untreated and WEDM-treated Invar-36 surfaces were reciprocated against an alumina ball at a sliding velocity of 40 mm/s, a stroke length of 10 mm and a sliding duration of 125 min under loads of 5, 10 and 20 N. The worn surfaces were characterized using a 2D profilometry and a scanning electron microscope equipped with energy-dispersive spectroscopy.

Findings

The results showed that the WEDM-treated surface had a superior friction coefficient and wear resistance in comparison to the untreated surface, due to the grown HAZ. There was found to be a 9.3%–11.4% decrease in the friction coefficient and a 47%–57% reduction in the wear volume after the WEDM treatment. Both the untreated and WEDM-treated Invar-36 surfaces found abrasion and plastic deformation as the dominant wear mechanisms.

Originality/value

Previous works have not focused on the tribological performance of the WEDM-treated Invar-36 extensively used for molding tools in aerospace industries. Our findings provide compelling evidence that the WEDM treatment improved the wear and friction performance of Invar-36 alloy because of the grown HAZ.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

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