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1 – 10 of 45Md.Tanvir Ahmed, Hridi Juberi, A.B.M. Mainul Bari, Muhommad Azizur Rahman, Aquib Rahman, Md. Ashfaqur Arefin, Ilias Vlachos and Niaz Quader
This study aims to investigate the effect of vibration on ceramic tools under dry cutting conditions and find the optimum cutting condition for the hardened steel machining…
Abstract
Purpose
This study aims to investigate the effect of vibration on ceramic tools under dry cutting conditions and find the optimum cutting condition for the hardened steel machining process in a computer numerical control (CNC) lathe machine.
Design/methodology/approach
In this research, an integrated fuzzy TOPSIS-based Taguchi L9 optimization model has been applied for the multi-objective optimization (MOO) of the hard-turning responses. Additionally, the effect of vibration on the ceramic tool wear was investigated using Analysis of Variance (ANOVA) and Fast Fourier Transform (FFT).
Findings
The optimum cutting conditions for the multi-objective responses were obtained at 98 m/min cutting speed, 0.1 mm/rev feed rate and 0.2 mm depth of cut. According to the ANOVA of the input cutting parameters with respect to response variables, feed rate has the most significant impact (53.79%) on the control of response variables. From the vibration analysis, the feed rate, with a contribution of 34.74%, was shown to be the most significant process parameter influencing excessive vibration and consequent tool wear.
Research limitations/implications
The MOO of response parameters at the optimum cutting parameter settings can significantly improve productivity in the dry turning of hardened steel and control over the input process parameters during machining.
Originality/value
Most studies on optimizing responses in dry hard-turning performed in CNC lathe machines are based on single-objective optimization. Additionally, the effect of vibration on the ceramic tool during MOO of hard-turning has not been studied yet.
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Milena Kiliszkiewicz, Dariusz Przybylski, Jan Felba and Ryszard Korbutowicz
The purpose of this paper is to analyze the individual steps during the printing of capacitor structures. The method of substrate preparation, the obtained roughness of conductive…
Abstract
Purpose
The purpose of this paper is to analyze the individual steps during the printing of capacitor structures. The method of substrate preparation, the obtained roughness of conductive and dielectric layers are examined. Moreover, the capacitances of the obtained capacitors were examined.
Design/methodology/approach
Surface roughness and microscopic analysis were used to assess the quality of printed conductive structures. Two criteria were used to assess the quality of printed dielectric structures: the necessary lack of discontinuity of layers and minimal roughness. To determine the importance of printing parameters, a draft experimental method was proposed.
Findings
The optimal way to clean the substrate has been determined. The most important parameters for the dielectric layer (i.e. drop-space, table temperature, curing time and temperature) were found.
Research limitations/implications
If dielectric layers are printed correctly, most problems with printing complex electronic structures (transistors, capacitors) will be eliminated.
Practical implications
The tests performed identified the most important factors for dielectric layers. Using them, capacitors of repeatable capacity were printed.
Originality/value
In the literature on this subject, no factors were found which were responsible for obtaining homogeneous dielectric layers.
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Alessandro Bove, Fulvio Lieske, Flaviana Calignano and Luca Iuliano
Material extrusion (MEX) is one of the most known techniques in the additive manufacturing (AM) sector to produce components with a wide range of polymeric and composite…
Abstract
Purpose
Material extrusion (MEX) is one of the most known techniques in the additive manufacturing (AM) sector to produce components with a wide range of polymeric and composite materials. Moisture causes alterations in material properties and for filaments strongly hygroscopic like nylon-based composites this means greater ease of deterioration. Drying the filament to reduce the moisture content may not be sufficient if the humidity is not controlled during printing. The purpose of this study is to achieve the recovery of a commercial nylon-based composite filament by applying process optimization using an open source MEX machine.
Design/methodology/approach
A statistical approach based on Taguchi’s method allowed to achieve an ultimate tensile strength (UTS). A verification of the geometrical capabilities of the process has been performed according to the standard ISO/ASTM 52902-2019. Chemical tests were also carried out to test the resistance to corrosion in acid and basic solutions.
Findings
An UTS of 71.37 MPa was obtained, significantly higher than the value declared by the filament’s manufacturer (Stratasys Inc., USA). The best configuration of process parameters leads to good geometrical deviations for flat surfaces, in a range of 0.01 and 0.38 for flatness, while cylindrical faces showed more important deviations from the nominal values. The good applicability of the material in corrosive environments has been confirmed.
Originality/value
This study examined the performance restoration potential of a nylon composite filament that was significantly affected by storage conditions. For the filament manufacturer, if the material remains in ambient air for an hour or idle in the machine for more than 24 h, the material may no longer be suitable for printing. The study highlighted that the drying of the filament must not be temporary but constant to guarantee printability, and, by acting on the process parameters, it is possible to obtain better mechanical properties than declared by the manufacturer.
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Hannele Kauppinen-Räisänen, Daleen van der Merwe and Magdalena Bosman
The aim of this study is to explore the contextual influences of packaging design and its cues on respondents' preferences.
Abstract
Purpose
The aim of this study is to explore the contextual influences of packaging design and its cues on respondents' preferences.
Design/methodology/approach
To explore the contextuality of packaging cues, a multi-attribute valuation technique, conjoint analysis was used for two types of pharmaceutical products (painkiller and sore throat medicine) across seven countries. Data were collected among respondents (N = 461) from Finland, Ghana, Mongolia, Nigeria, Portuguese, South Africa and the USA.
Findings
Similarities and dissimilarities were observed between the product types and countries analysed in terms of the impact of packaging cues. The findings demonstrate the global and local nature of brand cues expressed in retail packaging.
Practical implications
The study implies that some cues may serve global markets, while some cues may need to be localised in order to meet the needs of local markets. Understanding these cues and their influences on consumers' brand preferences and choices at the point-of-purchases may enable companies to enter new markets, help them create sustainable and credible global brands.
Originality/value
The study contributes to the existing retail packaging literature and pharmaceutical branding literature by providing empirical evidence of the multidimensional aspects of sensory packaging cues. Second, it contributes by showing the contextual nature of retail packaging and its associated cues for OTC pharmaceuticals.
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Abstract
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Fredrick Mwania, Maina Maringa, Joseph Nsengimana and Jacobus Gert van der Walt
The current analysis was conducted to investigate the quality of surfaces and geometry of tracks printed using PolyMideTM CoPA, PolymaxTM PC and PolyMideTM PA6-CF materials…
Abstract
Purpose
The current analysis was conducted to investigate the quality of surfaces and geometry of tracks printed using PolyMideTM CoPA, PolymaxTM PC and PolyMideTM PA6-CF materials through fused deposition modelling (FDM). This study also examined the degree of fusion of adjacent filaments (tracks) to approximate the optimal process parameters of the three materials.
Design/methodology/approach
Images of fused adjacent filaments were acquired using scanning electron microscopy (SEM), after which, they were analysed using Image J Software and Minitab Software to determine the optimal process parameters.
Findings
The optimal process parameters for PolyMideTM CoPA are 0.25 mm, 40 mm/s, −0.10 mm, 255°C and 0.50 mm for layer thickness, printing speed, hatch spacing, extrusion temperature and extrusion width, respectively. It was also concluded that the optimal process parameters for PolymaxTM PC are 0.30 mm, 40 mm/s, 0.00 mm, 260°C and 0.6 mm for layer thickness, printing speed, hatch spacing, extrusion temperature and extrusion width, respectively.
Research limitations/implications
It was difficult to separate tracks printed using PolyMideTM PA6-CF from the support structure, making it impossible to examine and determine their degree of fusion using SEM.
Social implications
The study provides more knowledge on FDM, which is one of the leading additive manufacturing technology for polymers. The information provided in this study helps in continued uptake of the technique, which can help create job opportunities, especially among the youth and young engineers.
Originality/value
This study proposes a new and a more accurate method for optimising process parameters of FDM at meso-scale level.
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Ranvijay Kumar, Rupinder Singh and Ilenia Farina
Three-dimensional printing (3DP) is an established process to print structural parts of metals, ceramic and polymers. Further, multi-material 3DP has the potentials to be a…
Abstract
Purpose
Three-dimensional printing (3DP) is an established process to print structural parts of metals, ceramic and polymers. Further, multi-material 3DP has the potentials to be a milestone in rapid manufacturing (RM), customized design and structural applications. Being compatible as functionally graded materials in a single structural form, multi-material-based 3D printed parts can be applied in structural applications to get the benefit of modified properties.
Design/methodology/approach
The fused deposition modelling (FDM) is one of the established low cost 3DP techniques which can be used for printing functional/ non-functional prototypes in civil engineering applications.
Findings
The present study is focused on multi-material printing of primary recycled acrylonitrile butadiene styrene (ABS), polylactic acid (PLA) and high impact polystyrene (HIPS) in composite form. Thermal (glass transition temperature and heat capacity) and mechanical properties (break load, break strength, break elongation, percentage elongation at break and Young’s modulus) have been analysed to observe the behaviour of multi-material composites prepared by 3DP. This study also highlights the process parameters optimization of FDM supported with photomicrographs.
Originality/value
The present study is focused on multi-material printing of primary recycled ABS, PLA and HIPS in composite form.
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Chongjun Wu, Yutian Chen, Xinyi Wei, Junhao Xu and Dongliu Li
This paper is devoted to prepare micro-cone structure with variable cross-section size by Stereo Lithography Appearance (SLA)-based 3D additive manufacturing technology. It is…
Abstract
Purpose
This paper is devoted to prepare micro-cone structure with variable cross-section size by Stereo Lithography Appearance (SLA)-based 3D additive manufacturing technology. It is mainly focused on analyzing the forming mechanism of equipment and factors affecting the forming quality and accuracy, investigating the influence of forming process parameters on the printing quality and optimization of the printing quality. This study is expected to provide a µ-SLA surface preparation technology and process parameters selection with low cost, high precision and short preparation period for microstructure forming.
Design/methodology/approach
The µ-SLA process is optimized based on the variable cross-section micro-cone structure printing. Multi-index analysis method was used to analyze the influence of process parameters. The process parameter influencing order is determined and validated with flawless micro array structure.
Findings
After the optimization analysis of the top diameter size, the bottom diameter size and the overall height, the influence order of the printing process parameters on the quality of the micro-cone forming is: exposure time (B), print layer thickness (A) and number of vibrations (C). The optimal scheme is A1B3C1, that is, the layer thickness of 5 µm, the exposure time of 3000 ms and the vibration of 64x. At this time, the cone structure with the bottom diameter of 50 µm and the cone angle of 5° could obtain a better surface structure.
Originality/value
This study is expected to provide a µ-SLA surface preparation technology and process parameters selection with low cost, high precision and short preparation period for microstructure forming.
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