Search results
1 – 6 of 6Tunay Turk, Cesar E. Dominguez, Austin T. Sutton, John D. Bernardin, Jonghyun Park and Ming C. Leu
This paper aims to present spot pattern welding (SPW) as a scanning strategy for laser-foil-printing (LFP) additive manufacturing (AM) in place of the previously used continuous…
Abstract
Purpose
This paper aims to present spot pattern welding (SPW) as a scanning strategy for laser-foil-printing (LFP) additive manufacturing (AM) in place of the previously used continuous pattern welding (CPW) (line-raster scanning). The SPW strategy involves generating a sequence of overlapping spot welds on the metal foil, allowing the laser to form dense and uniform weld beads. This in turn reduces thermal gradients, promotes material consolidation and helps mitigate process-related risks such as thermal cracking, porosity, keyholing and Marangoni effects.
Design/methodology/approach
304L stainless steel (SS) feedstock is used to fabricate test specimens using the LFP system. Imaging techniques are used to examine the melt pool dimensions and layer bonding. In addition, the parts are evaluated for residual stresses, mechanical strength and grain size.
Findings
Compared to CPW, SPW provides a more reliable heating/cooling relationship that is less dependent on part geometry. The overlapping spot welds distribute heat more evenly, minimizing the risk of elevated temperatures during the AM process. In addition, the resulting dense and uniform weld beads contribute to lower residual stresses in the printed part.
Originality/value
To the best of the authors’ knowledge, this is the first study to thoroughly investigate SPW as a scanning strategy using the LFP process. In general, SPW presents a promising strategy for securing embedded sensors into LFP parts while minimizing residual stresses.
Details
Keywords
Manjunatha M. and Kavitha T.S.
The purpose of this study is to investigate the behaviour of M40 grade of self-compacting concrete (SCC) with high volume of ground granulated blast furnace slag (GGBS) (50%) and…
Abstract
Purpose
The purpose of this study is to investigate the behaviour of M40 grade of self-compacting concrete (SCC) with high volume of ground granulated blast furnace slag (GGBS) (50%) and recycled concrete aggregate (RCA) content up to 100% to assess the mechanical properties of SCC. As per guidelines of IS: 383 – 2016, the RCA can be replaced up to 20% of natural coarse aggregate up to M25 grade of concrete. This study assesses the mechanical properties of SCC beyond 20% of RCA content. Based on the experimental investigations, the compressive strength of mixes decreases as the content of RCA increases. It is found that concrete mixes with 20% RCA and shows the maximum compressive strength at 56 days.
Design/methodology/approach
The fresh properties as per EFNARC and IS: 10262–2019 guidelines, ultrasonic pulse velocity testing, mechanical properties and microstructure analysis have been conducted to evaluate the performance of SCC with RCA for practical applications.
Findings
From the experimental investigations, it is found that up to 50% of recycled coarse aggregate can be used for structural applications.
Originality/value
The environmental pollution and dumping of waste on green land can be reduced by effective utilization of recycled coarse aggregate and GGBS in the production of SCC.
Details
Keywords
Bataa Sayed Mohamed Mazen, Badawi Mohamed Ismail, Rushdya Rabee Ali Hassan, Mahmoud Ali and Wael S. Mohamed
The purpose of this study is to detect the effect of some natural cellulosic polymers in their nano forms with the addition of zinc oxide nanoparticles on restoring the lost…
Abstract
Purpose
The purpose of this study is to detect the effect of some natural cellulosic polymers in their nano forms with the addition of zinc oxide nanoparticles on restoring the lost mechanical strength of degraded papyrus without any harmful effects on the inks.
Design/methodology/approach
In the current study, the USB digital microscopy, scanning electron microscope, measurement of mechanical properties (tensile and elongation), pH measurement, color change and infrared spectroscopy were undertaken for the samples before and after treatment and aging.
Findings
In the current study, the USB digital microscopy, scanning electron microscope, measurement of mechanical properties (tensile and elongation), pH measurement, color change and infrared spectroscopy were undertaken for the samples before and after treatment and aging.
Originality/value
The effect of strengthening materials was studied on cellulose and carbon ink, which makes this study closer to reality as the manuscript is the consistent structure of cellulose and inks, whereas most of the literature stated the impact of consolidation materials on the strengthening the cellulosic supports without attention to their impact on inks.
Details
Keywords
Veluchamy M., Kumanan Somasundaram and Satheeshkumar V.
The purpose of this paper is to investigate the friction and wear mechanisms in lubricated sliding conditions of additively manufactured SS316L parts. The different viscous oils…
Abstract
Purpose
The purpose of this paper is to investigate the friction and wear mechanisms in lubricated sliding conditions of additively manufactured SS316L parts. The different viscous oils 5W30, 15W40, 20W50 and SAE140 are used. These investigations provide a theoretical basis for the high performance of printed and postheattreated SS316L.
Design/methodology/approach
Tribological tests were carried out on selective laser melting-made SS316L printed specimens and heat-treated specimens. The parameters in 15 min of test duration are 20 N of load, 200 rpm, 8 mm of pin diameter, 25 mm length, 80 mm of track diameter and EN31 counter disc body. This work presented the phenomena of lubrication regimes and their characterization, as identified by the Stribeck curve, and these regimes affect the tribological properties of additively manufactured SS316L under the influence of industrial viscous lubricants. The results are observed using Scanning electron microscope (SEM), X-ray diffraction (XRD) and wear tests.
Findings
The observations indicate that additively manufactured SS316L shows a reduced coefficient of friction (COF) and specific wear rate (SWR). This is credited to the utilization of different viscous lubricants.
Originality/value
This exclusive research demonstrates how various viscous lubricants affect the COF and SWR of printed and post-heat-treated SS316L parts. Lambda (λ), lubricant film thickness (h0), surface roughness and wear mechanisms are studied and reported.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0110/
Details
Keywords
Asmaa Abu Qaadan, Faten Hamad and Hussam Fakhouri
This study examines the digital accessibility of information services for students with disabilities at the University of Jordan. Despite advancements in disability rights and…
Abstract
Purpose
This study examines the digital accessibility of information services for students with disabilities at the University of Jordan. Despite advancements in disability rights and technology, academic libraries often lag in providing fully accessible digital services.
Design/methodology/approach
The mixed-methods research involved quantitative surveys from 173 students with disabilities and a qualitative interview with the head of the information application department, in addition to a focus group interview with 10 students with disabilities. Quantitative analysis included means, standard deviations and four-way ANOVA to identify significant differences in perceptions. Qualitative insights highlighted specific issues and recurring themes, revealing significant gaps in digital accessibility.
Findings
The results revealed a weak level of digital accessibility of students with disabilities to information services in academic libraries in Jordan is very low. The findings indicate a need for improvements in library infrastructure, staff training and policy development. The study also offers insights into challenges in a developing country context and provides recommendations for enhancing library inclusivity and support structures, emphasizing the importance of aligning services with international accessibility standards.
Practical implications
The findings will primarily be beneficial for library managers to understand their library’s deficiencies and responsibility towards the local community and the enhancement of digital inclusion. This understanding will aid in planning training programs and workshops for employees on supporting students with disabilities. Additionally, it serves as a valuable resource for collaboration between libraries and educators to organize educational sessions for academic librarians in Jordan and other developing nations.
Originality/value
It serves as a valuable resource for collaboration between libraries and educators to organize educational sessions for academic librarians in Jordan and other developing nations. This research adds value to existing literature by highlighting the context in one developing country.
Details
Keywords
Ketshepileone Shiela Matlhoko, Jana Franie Vermaas, Natasha Cronjé and Sean van der Merwe
The South African wool industry is integral to the country's agricultural sector, particularly sheep farming and wool production. Small-scale farmers play a vital role in this…
Abstract
Purpose
The South African wool industry is integral to the country's agricultural sector, particularly sheep farming and wool production. Small-scale farmers play a vital role in this industry and contribute to employment and food security in rural communities. However, these farmers face numerous challenges, including a lack of funding, poor farming practices and difficulty selling their wool at fair prices. This study aims to address these challenges, the University of Free State launched a wool value chain project for small-scale farmers.
Design/methodology/approach
In this project, one of the studies conducted assessed the effectiveness of different detergents suitable for traditional wool scouring methods for small-scale farmers who lack access to sophisticated machinery. The investigation was conducted by scouring 160 wool samples using three different detergents and filtered water as a control. The wool samples were then evaluated for their cleanliness, brightness and fibre properties through a combination of scanning electron microscopy, spectrophotometry and statistical analysis at different scouring times (3, 10, 15 and 20 min, respectively).
Findings
The results showed that the combination of scouring time and the type of scouring solution used could significantly impact wool quality. It was found that using a combination of standard detergent or Woolwash as a scouring solution with a scouring time of 10–15 min resulted in the best outcome in terms of fibre property, wool colour and scouring loss.
Originality/value
This study demonstrated that traditional wool scouring methods could be an option for small-scale farmers and anyone who want to learn how to scour wool without expensive machinery to make wool products.
Details