Search results

1 – 10 of 13
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 14 March 2023

Lei Wan, Jian Xu, Yulai Li, Haiou Sun and Tao Zhang

The purpose of this paper is to improve the corrosion resistance of anodized 6063 Al alloy inertial air–water separator by means of silane technology and to investigate the effect…

246

Abstract

Purpose

The purpose of this paper is to improve the corrosion resistance of anodized 6063 Al alloy inertial air–water separator by means of silane technology and to investigate the effect of corrosion-generated surface roughness changes on aerodynamic performance.

Design/methodology/approach

The BTSE-KH560 double-layer silane film treatment technique is used to close micropores on the anodic oxide film surface. The microstructure of the coating is observed by scanning electron microscopy, the coating structure of the specimens is determined by X-ray diffraction (XPS) and the corrosion resistance is determined by electrochemical and salt-spray tests. Computational fluid dynamics is also used to calculate the effect of roughness and analyse the change in separator performance.

Findings

The silane film deposited on the surface of the anodic oxide film acts as a good seal against microporous defects on the surface of the anodic oxide film and reduces the surface roughness. Electrochemical and salt-spray tests show that the silane film improved the corrosion resistance of the anodized film. The roughness produced by the corrosion deteriorates the performance of the separator.

Originality/value

The porous structure of the anodized coating makes it easier for corrosive ions to enter the substrate and cause pitting corrosion. Therefore, in this study, the corrosion behaviour of the coating in the marine environment and its effect on aerodynamic performance are investigated using a BTSE-KH560 double-layer silane coating with a sealing effect.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Access Restricted. View access options
Article
Publication date: 14 December 2022

Runyao Yu, Xingwang Bai, Xueqi Yu and Haiou Zhang

A new wire arc additive manufacturing (WAAM) process combined with gravity-driven powder feeding was developed to fabricate components of tungsten carbide (WC)-reinforced iron…

277

Abstract

Purpose

A new wire arc additive manufacturing (WAAM) process combined with gravity-driven powder feeding was developed to fabricate components of tungsten carbide (WC)-reinforced iron matrix composites. The purpose of this study was to investigate the particle transportation mechanism during deposition and determine the effects of WC particle size on the microstructure and properties of the so-fabricated component.

Design/methodology/approach

Thin-walled samples were deposited by the new WAAM using two WC particles of different sizes. A series of in-depth investigations were conducted to reveal the differences in the macro morphology, microstructure, tensile performance and wear properties.

Findings

The results showed that inward convection and gravity were the main factors affecting WC transportation in the molten pool. Large WC particles have higher ability than small particles to penetrate into the molten pool and survive severe dissolution. Small WC particles were more likely to be completely dissolved around the top surface, forming a thicker region of reticulate (Fe, W)6C. Large WC particles can slow down the inward convection more, thereby leading to an increase in width and a decrease in the layer height of the weld bead. The mechanical properties and wear resistance significantly increased owing to reinforcement. Comparatively, samples with large WC particles showed inferior tensile properties owing to their higher susceptibility to cracks.

Originality/value

Fabricating metal matrix composites through the WAAM process is a novel concept that still requires further investigation. Apart from the self-designed gravity-driven powder feeding, the unique aspects of this study also include the revelation of the particle transportation mechanism of WC particles during deposition.

Details

Rapid Prototyping Journal, vol. 29 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 26 April 2023

Mudassar Rehman, Yanen Wang, Kashif Ishfaq, Haiou Yang, Ray Tahir Mushtaq, M. Saravana Kumar and Ammar Ahmed

Since the biomedical implants with an improved compressive strength, near bone elastic modulus, controlled porosity, and sufficient surface roughness, can assist in long term…

287

Abstract

Purpose

Since the biomedical implants with an improved compressive strength, near bone elastic modulus, controlled porosity, and sufficient surface roughness, can assist in long term implantation. Therefore, the fine process tuning plays its crucial role to develop optimal settings to achieve these desired properties. This paper aims to find applications for fine process tuning in laser powder bed fusion of biomedical Ti alloys for load-bearing implants.

Design/methodology/approach

In this work, the parametric porosity simulations were initially performed to simulate the process-induced porosity for selective laser-melted Ti6Al4V as per full factorial design. Continually, the experiments were performed to validate the simulation results and perform multiresponse optimization to fine-tune the processing parameters. Three levels of each control variable, namely, laser power – Pl (180, 190, 200) W, scanning speed – Vs (1500, 1600, 1700) mm/s and scan orientation – ϴ{1(0,0), 2(0,67°), 3(0,90°)} were used to investigate the processing performance. The measured properties from this study include compressive yield strength, elastic modulus, process-induced porosity and surface roughness. Finally, confirmatory experiments and comparisons with the already published works were also performed to validate the research results.

Findings

The results of porosity parametric simulation and experiments in selective laser melting of Ti6Al4V were found close to each other with overall porosity (less than 10%). The fine process tuning was resulted in optimal settings [Pl (200 W), Vs (1500 mm/s), ϴ (0,90°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,67°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] and [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] with higher compressive strength (672.78 MPa), near cortical bone elastic modulus (12.932 GPa), process-induced porosity (0.751%) and minimum surface roughness (2.72 µm). The morphology of the selective laser melted (SLMed) surface indicated that the lack of fusion pores was prominent because of low laser energy density among the laser and powder bed. Confirmatory experimentation revealed that an overall percent improvement of around 15% was found between predicted and the experimental values.

Originality/value

Since no significant works are available on the collaborative optimization and fine process tuning in laser powder bed fusion of biomedical Ti alloys for different load bearing implants. Therefore, this work involves the comprehensive investigation and multi-objective optimization to determine optimal parametric settings for better mechanical and physical properties. Another novel aspect is the parametric porosity simulation using Ansys Additive to assist in process parameters and their levels selection. As a result, selective laser melted Ti alloys at optimal settings may help in examining the possibility for manufacturing metallic implants for load-bearing applications.

Details

Rapid Prototyping Journal, vol. 29 no. 6
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 1 October 2021

Xi Chen, Youheng Fu, Fanrong Kong, Runsheng Li, Yu Xiao, Jiannan Hu and Haiou Zhang

The major problem that limits the widespread use of WAAM technology is the forming quality. However, most of the current research focuses on post-process detections that are…

536

Abstract

Purpose

The major problem that limits the widespread use of WAAM technology is the forming quality. However, most of the current research focuses on post-process detections that are time-consuming, expensive and destructive. This paper aims to achieve the on-line detection and classification of the common defects, including hump, deposition collapse, deviation, internal pore and surface slag inclusion.

Design/methodology/approach

This paper proposes an in-process multi-feature data fusion nondestructive testing method based on the temperature field of the WAAM process. A thermal imager is used to collect the temperature data of the deposition layer in real-time. Efficient processing methods are proposed in this paper, such as the temperature stack algorithm, width extraction algorithm and a classification model based on a residual neural network. Some features closely related to the forming quality were extracted, containing the profile image and width curve of the deposition layer and abnormal temperature features in longitudinal and cross-sections. These features are used to achieve the detection and classification of defects.

Findings

Thermal non-destructive testing is a potentially superior technology for in-process detection in the industrial field. Based on the temperature field, extracting the most relevant features of the defect information is crucial. This paper pushes current infrared (IR) monitoring methods toward real-time detection and proposes an in-process multi-feature data fusion non-destructive testing method based on the temperature field of the WAAM process.

Originality/value

In this paper, the single-layer and multi-layer WAAM samples are preset with various defects, such as hump, deposition collapse, deviation, pore and slag inclusion. A multi-feature nondestructive testing methodology is proposed to realize the in-process detection and classification of the defects. A temperature stack algorithm is proposed, which improves the detection accuracy of profile change and solves the problem of uneven temperature from arc striking to arc extinguishing. The combination of residual neural network greatly improves the accuracy and efficiency of detection.

Details

Rapid Prototyping Journal, vol. 28 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 4 November 2022

Ruizhe Wang, Runsheng Li, Guilan Wang, Mingbo Zhang, Jianwu Huang, Hang Lin and Haiou Zhang

Wire and arc additive manufacturing (WAAM) technology-based cold metal transfer (CMT) to produce large aluminum alloy parts has become more and more popular. In WAAM, wire is the…

188

Abstract

Purpose

Wire and arc additive manufacturing (WAAM) technology-based cold metal transfer (CMT) to produce large aluminum alloy parts has become more and more popular. In WAAM, wire is the only raw material. The purpose of this paper is to study the effect of wire composition on the microstructure and properties of the ZAlCu5MnCdVA alloy deposited by WAAM.

Design/methodology/approach

Two thin-walled ZAlCu5MnCdVA alloys with different wire compositions were prepared by WAAM. The copper contents were 4.7% (Al-4.7Cu) and 5.0% (Al-5.0Cu), respectively. The microstructure, element distribution and evolution of precipitated phases of the two samples were characterized and analyzed by optical microscopy, scanning electron microscopy and transmission electron microscopy. Hardness and tensile properties of samples were tested, and strengthening mechanism was analyzed in detail.

Findings

The results show that grain sizes of Al-4.7Cu and Al-5.0Cu are less than 40 μm. The average mass fraction of Cu in Al matrix and the number of nanometer scale θ'' and θ' phases are the main factors affecting the tensile properties of Al-Cu alloy. Tensile properties of two materials show different characteristics at room temperature and high temperature. Al-5.0Cu is better at room temperature and Al-4.7Cu is better at high temperature. The yield strength (YS), ultimate tensile strength (UTS) and elongation in the x direction of Al-5.0Cu at room temperature are 451 ± 10.2 MPa, 486 ± 10.2 MPa and 9 ± 0.5%, respectively. The YS, UTS and elongation in the x direction of Al-4.7Cu at high temperature are 290 ± 4.5 MPa, 356 ± 7.0 MPa and 13% ± 0.2%, respectively.

Originality/value

Experiments show that the increase of Cu element can improve the properties at room temperature of the ZAlCu5MnCdVA alloy by WAAM, but its properties at high temperature decrease.

Details

Rapid Prototyping Journal, vol. 29 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 13 April 2022

Qingyong Chen, Guilan Wang, Haiou Zhang and Runsheng Li

The purpose of this paper is to study the influence of different rolling deformation parameters on the morphology, microstructure and mechanical properties of Inconel 718…

275

Abstract

Purpose

The purpose of this paper is to study the influence of different rolling deformation parameters on the morphology, microstructure and mechanical properties of Inconel 718 superalloy in hybrid plasma arc and micro-rolling (HPAMR) additive manufacturing.

Design/methodology/approach

In this paper, different deformation strains are designed, which are as-deposited, 15% and 30%. Two straight walls are fabricated by HPAMR for each kind of deformation. One wall underwent post-deposition heat treatment, and the other wall is treated without heat treatment. These samples are further investigated to evaluate the effects of deformation on the morphology, microstructure and mechanical properties.

Findings

As compared to as-deposited samples, the morphology can be significantly improved, the generation of defects and microporosity inside the alloy can be suppressed, and finer equiaxed crystals can be obtained with deformation of 30%. With heat treatment and 30% deformation, the Laves phase at the grain boundary is completely disappearing, more γ” and γ' strengthening phase is precipitated in the crystal and the size of the strengthening phase is smaller. Mechanical properties have been significantly improved.

Practical implications

HPAMR technology is used to successfully manufacture Inconel 718 superalloy aero-engine casing.

Originality/value

Compared with plasma arc additive manufacturing, HPAMR technology adds a rolling process, which can effectively improve the morphology of walls, refine internal grains, eliminate defects and microporosity, increase precipitation of strengthening phase and improve mechanical properties. It provides an optional manufacturing method for the integrated manufacturing of Inconel 718 parts.

Details

Rapid Prototyping Journal, vol. 28 no. 8
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 30 October 2019

Runsheng Li, Haiou Zhang, Fusheng Dai, Cheng Huang and Guilan Wang

Large-scale aircraft parts usually with many frame features, which consist of intersections. Profile and tensile properties of junctions in wire and arc additive manufacturing…

517

Abstract

Purpose

Large-scale aircraft parts usually with many frame features, which consist of intersections. Profile and tensile properties of junctions in wire and arc additive manufacturing (WAAM) are significantly affected by path strategies. The purpose of this paper is to propose a novel path strategy for intersections in WAAM and compare it with commonly used ones.

Design/methodology/approach

Three typical intersections including T crossing (TC), square crossing (SC) and arbitrary-angle crossing (AAC) were built up with two commonly used path strategies (parallel and oscillation) and a proposed method named end lateral extension (ELE) which extends the weld track along the crossed direction. A robotic system and cold metal transfer (CMT) process were used to deposit Al-6.3Cu (2319) alloy. The profile of the bead was scanned by laser vision sensor. Tightened ratio (r), inter-layer height increment (Δh) and deviation to the fitting plane (df) are calculated based on the point cloud. Tensile tests were done for all built intersections.

Findings

Comparison to the commonly used path strategies, the proposed ELE method eliminated the tightened defects at the intersection, achieved a more stable inter-layer height increment (Δh) and improved the profile quality with a lower deviation to the fitting plane (df). Tensile tests show that the proposed strategy has exhibited favorable tensile properties.

Originality/value

In this paper, a novel path strategy named ELE is proposed, which provides a new path choice for fabricating intersections by WAAM.

Details

Rapid Prototyping Journal, vol. 26 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 4 January 2021

Shangyong Tang, Guilan Wang, Hao Song, Runsheng Li and Haiou Zhang

Modeling and control of bead geometry in wire and arc additive manufacturing is significant as it affects the whole manufacturing process. The purpose of this paper is to…

790

Abstract

Purpose

Modeling and control of bead geometry in wire and arc additive manufacturing is significant as it affects the whole manufacturing process. The purpose of this paper is to establish an efficient model to control the bead geometry with fewer experiments in wire and arc additive manufacturing (WAAM).

Design/methodology/approach

A multi-sensor system is established to monitor the process parameters and measure the bead geometry information. A dynamic parameters experimental method is proposed for rapid modeling without dozens of experiments. A deep learning method is used for bead modeling and control. To adaptively control the bead geometry in real-time, a closed-loop control system was developed based on the bead model and in situ monitoring.

Findings

A series of experiments were conducted to train, test and verify the feasibility of the method and system, and the results showed that the proposed method can build the bead model rapidly with high precision, and the closed-loop system can control the forming geometry adaptively.

Originality/value

The proposed modeling method is novel as the experiment number is reduced. The dynamic parameters experimental method is effective with high precision. The closed-loop control system can control the bead geometry in real-time. The forming accuracy is elevated.

Details

Rapid Prototyping Journal, vol. 27 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 27 September 2021

Xushan Zhao, Yuanxun Wang, Guilan Wang, Runsheng Li and Haiou Zhang

This paper aims to summarize the influence law of hybrid deposited and micro-rolling (HDMR) technology on the shaping strain and residual stress. And the rolling parameters…

267

Abstract

Purpose

This paper aims to summarize the influence law of hybrid deposited and micro-rolling (HDMR) technology on the shaping strain and residual stress. And the rolling parameters combination was further optimized to guide the actual production.

Design/methodology/approach

This paper proposed a three-dimensional coupled thermo-mechanical model of the HDMR process. The validated model is used to investigate the influences of rolling parameters on stress and plastic strain (the distance between the energy source and roller [De–r], the rolling compression [cr] and the friction coefficient [fr]). The orthogonal optimization of three factors and three levels was carried out. The influence of rolling parameters on the plastic strain and residual stress is analyzed.

Findings

The simulation results show that HDMR technology can effectively increase the shaping strain of the weld bead and reduce the residual tensile stress on the weld bead surface. Furthermore, the influence of rolling parameters on stress and strain is obtained by orthogonal analysis, and the corresponding optimal combination is proposed. Also, the rolling temperature significantly affects the residual stress, and the rolling reduction has a substantial effect on the plastic deformation.

Research limitations/implications

Owing to the choice of research methods, this paper failed to study microstructure evolution.

Originality/value

This paper provides a reference principle for the optimal selection of rolling parameters in HDMR.

Details

Rapid Prototyping Journal, vol. 28 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 15 November 2022

Jun Wu, Cheng Huang, Zili Li, Runsheng Li, Guilan Wang and Haiou Zhang

Wire and arc additive manufacturing (WAAM) is a widely used advanced manufacturing technology. If the surface defects occurred during welding process cannot be detected and…

443

Abstract

Purpose

Wire and arc additive manufacturing (WAAM) is a widely used advanced manufacturing technology. If the surface defects occurred during welding process cannot be detected and repaired in time, it will form the internal defects. To address this problem, this study aims to develop an in situ monitoring system for the welding process with a high-dynamic range imaging (HDR) melt pool camera.

Design/methodology/approach

An improved you only look once version 3 (YOLOv3) model was proposed for online surface defects detection and classification. In this paper, improvements were mainly made in the bounding box clustering algorithm, bounding box loss function, classification loss function and network structure.

Findings

The results showed that the improved model outperforms the Faster regions with convolutional neural network features, single shot multibox detector, RetinaNet and YOLOv3 models with mAP value of 98.0% and a recognition rate of 59 frames per second. And it was indicated that the improved YOLOv3 model satisfied the requirements of real-time monitoring well in both efficiency and accuracy.

Originality/value

Experimental results show that the improved YOLOv3 model can solve the problem of poor performance of traditional defect detection models and other deep learning models. And the proposed model can meet the requirements of WAAM quality monitoring.

1 – 10 of 13
Per page
102050