Sanna F. Siddiqui and Ali P. Gordon
Additive manufacturing (AM) studies on Inconel 718 (IN718) have focused on exploring its tensile and fatigue response. As IN718 is used in the propulsion and energy sector, the…
Abstract
Purpose
Additive manufacturing (AM) studies on Inconel 718 (IN718) have focused on exploring its tensile and fatigue response. As IN718 is used in the propulsion and energy sector, the impact of shearing is also critical to ensuring the durability of these components. As such, this study aims to explore the relation between build orientation on the shear cyclic response of direct metal laser sintered (DMLS) IN718.
Design/methodology/approach
IN718 torsion specimens were manufactured along six build orientations: (100)-X, (010)-Y, (001)-Z, (110)-XY45, (101)-XZ45 and (011)-YZ45, using the DMLS process. Torsional fatigue testing was performed on as-built specimens, from which fracture behavior, surface roughness, softening/hardening response and monotonic/cyclic shear torsional properties were assessed.
Findings
DMLS IN718 was found to exhibit transversely isotropic behavior. In terms of shear stress range and shear modulus, Z > (X, XY45, Y) > (XZ45, YZ45). Specimens cyclically hardened to stabilization and softened to fracture. In terms of torsional fatigue fracture response, the Z, XZ45 and YZ45 specimens exhibited crack initiation and propagation from internal defects, whereas cracks were found to initiate at the surface and propagate between and through build layers for the X, Y and XY45 specimens.
Originality/value
This study reports the torsional cyclic response and shear moduli exhibited by as-built DMLS IN718 manufactured along varying build orientations. The findings are applicable for researchers because of the wide use of IN718 in the gas turbine industry, and the current trend to replace conventional manufacturing with AM.
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Sanna F. Siddiqui, Andre Archer, Dustin Fandetti and Carl McGee
The aerospace, energy and automotive industries have seen wide use of composite materials because of their excellent mechanical properties, along with the benefit of weight…
Abstract
Purpose
The aerospace, energy and automotive industries have seen wide use of composite materials because of their excellent mechanical properties, along with the benefit of weight reduction savings. As such, the purpose of this study is to provide an understanding of the mechanical performance of these materials under extreme operational conditions characteristic of in-service environments.
Design/methodology/approach
This study is novel in that it has evaluated the tensile performance and fracture response of additively manufactured continuous carbon fiber embedded in an onyx matrix (i.e. nylon with chopped carbon fiber) at cryogenic and room temperatures, for specimens manufactured with an angle between the specimen lying plane and the working build plane of 0°, 45° and 90°.
Findings
Research findings reveal enhanced tensile properties (i.e. ultimate tensile strength and modulus of elasticity) by the 0° (X) built specimens, as compared with the 45° (XZ45) and 90° (Z) built specimens at cryogenic temperature. A reduction in ductility is observed at cryogenic temperature for all build orientations. Fractographic analysis reveals the presence of fiber pullout/elongation, pores within the onyx matrix and chopped carbon fiber near fracture zone of the onyx matrix.
Research limitations/implications
Research findings present tensile properties (i.e. ultimate tensile strength, modulus of elasticity and elongation%) for three-dimensional (3D)-printed onyx with and without reinforcing continuous carbon fiber composites at cryogenic and room temperatures. Reinforcement of continuous carbon fibers and reduction to cryogenic temperatures appears to result, in general, in an increase in the tensile strength and modulus of elasticity, with a reduction in elongation% as compared with the onyx matrix tensile performance reported at room temperature. Fracture analysis reveals continuous carbon fiber pull out for onyx–carbon fiber samples tested at room temperature and cryogenic temperatures, suggesting weak onyx matrix–continuous carbon fiber adhesion.
Originality/value
To the best of the authors’ knowledge, this study is the first study to report on the cryogenic tensile properties and fracture response exhibited by 3D-printed onyx–continuous carbon fiber composites. Evaluating the viability of common commercial 3D printing techniques in producing composite parts to withstand cryogenic temperatures is of critical import, for aerospace applications.
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Zulfiqar Ali Jumani and Sasiwemon Sukhabot
Multi-national corporations (MNC) are investing in Malaysia to serve Malay Muslims by carrying the tag line “we are Islamic” for their products. Academicians defined it, as…
Abstract
Purpose
Multi-national corporations (MNC) are investing in Malaysia to serve Malay Muslims by carrying the tag line “we are Islamic” for their products. Academicians defined it, as “Islamic brand/s”. Islamic brand/s further divided into three subcategories, namely, Islamic brand/s by compliance, Islamic brand/s by the customer and Islamic brand/s by country of origin. This study aims to identify the important aspect of the Islamic brand/s among the Malaysian Muslims, and it identifies, which Islamic brand aspect motivate Malay consumers to buy Islamic brands.
Design/methodology/approach
The conceptual model takes on in the current study was the theory of planned behaviour (TPB). The data was collected from three states of Malaysia (Penang, Kuala Lumpur and Johor Baharu) from 236 Malaysian Muslims through a structured survey instrument. Smart-partial least squares 3 statistical software was used for analyses.
Findings
Among Malaysian Muslims, the most important attitude is the Islamic brand/s by origin (country of origin) followed by the Islamic brand/s by the customer and Islamic brand/s by compliance.
Research limitations/implications
The study was conducted in three states of Malaysia, and the results are based on three attitudes of Islamic brands as independent variables and buying behavioural intentions (BI) construct of TPB.
Practical implications
Current study valuable for local businesses, MNCs, other Islamic and halal institutes. This study put light and give awareness of the positioning of the Islamic brand/s. Plus the intentions of users in selecting Islamic brand/s.
Originality/value
This research pursues to clarify consumers’ buying BIs in buying Islamic brand/s in Malaysia.
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Phattharatharaporn Singkheeprapha, Zulfiqar Ali Jumani and Sasiwemon Sukhabot
In southeast Asia, international companies are growing to serve customers with multiple faiths. This study aims to focus on Thailand and it is one of Southeast Asia’s nations and…
Abstract
Purpose
In southeast Asia, international companies are growing to serve customers with multiple faiths. This study aims to focus on Thailand and it is one of Southeast Asia’s nations and it has Muslim minority customers. To represent Thai Muslim companies, Thai Muslims are marketing their goods by bearing the tagline “we are Islamic”. Scholars described it as “Islamic brands”. This research describes the significant feature of Islamic brands between Thai Muslim people. It examines, which of the Islamic brand dimensions motivates Thai customers towards buying Islamic brands.
Design/methodology/approach
The current study’s conceptual model was the theory of planned behaviour (TPB) and 281 Thai Muslims responded via a standardised survey. The data was collected from four southern Thailand provinces (Narathiwat, Pattani, Satun and Yala) and the statistical application Smart-partial least-squares 3 was used for data analysis.
Findings
The most significant factor motivating Thai Muslims towards purchasing Islamic brands is the customer’s Islamic brand. The second factor was the Islamic brands by compliance and Islamic brands by country of origin.
Research limitations/implications
Three regions in Thailand have been researched, as well as the results concentrate only on three Islamic brand attitudes as independent variables and the development of behavioural expectations of TPB. This research also presents a model that could help understand the consumer perceptions about Islamic brands and established brands amongst various consumers.
Practical implications
The present research applies to small companies and multi-national businesses, as it illuminates and recognises the image of Islamic brands and suggests the preferences of customers in selecting the brand of Islamic brand.
Originality/value
The current study aims to explain Thai Muslim customers’ buying behavioural intentions while purchasing Islamic brands in Thailand.
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Anil Gupta, Honeyka Mahajan, Nikita Dogra and Ravinder Dogra
Drawing on the Push-Pull-Mooring model, this study sheds light on the factors that drive tourists to switch from traditional hotels to peer-to-peer accommodation (P2PA) in light…
Abstract
Purpose
Drawing on the Push-Pull-Mooring model, this study sheds light on the factors that drive tourists to switch from traditional hotels to peer-to-peer accommodation (P2PA) in light of the global spread of the Covid-19 pandemic.
Design/methodology/approach
Data have been collected from 380 participants through an online pan India survey. The data were mainly analyzed by adopting structural equation modeling.
Findings
All the three categories of push, pull and mooring factors are crucial in explaining tourists' switching intentions from hotels to P2PA. Out of all the factors, subjective norm came out to be the most significant factor while satiation (push factor) and authentic experiences (pull factor) also came out to be important indicators.
Practical implications
The findings of this study carry implications for hoteliers as well as P2PA platform hosts. Hotels need to re-conceptualize their standard services, décor and amenities while P2PA hosts need to continue providing authentic experiences and also comply with all the Covid-19 norms.
Originality/value
The study offers a comprehensive PPM model to determine tourists' intentions to switch from hotels to P2PA. Moreover, this paper is one of the early studies to provide insights into tourists' switching intentions amidst Covid-19.
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S. Sarkar and S. Chandra
Recent societal interest in healthful foods has led to the development of functional dairy products that basically provide health benefits in addition to their fundamental…
Abstract
Purpose
Recent societal interest in healthful foods has led to the development of functional dairy products that basically provide health benefits in addition to their fundamental nutrients. Yoghurt being most popular fermented milk product due to its healthy image can be an excellent carrier for probiotics. Functional properties of yoghurt can be enhanced with the inclusion of functional ingredients such as probiotics and its conjugate application with prebiotics may be advantageous as it favors probiotic growth. Nutritional and medicinal value of honey coupled with presence of oligosaccharides has projected honey as a functional additive in yoghurt.
Design/methodology/approach
Attempt has been made to review the literature on the biochemical activities of yoghurt cultures and probiotics in presence of honey. Both review and research papers related to biochemical activities and functional properties of yoghurt cultures and probiotics in presence of honey and their health benefits published in diverse journals under Pub Med and Science Direct have been considered. Keywords used for data search included functional foods, yoghurt, probiotic, health benefits, honey, etc.
Findings
Functional properties of yoghurt can be further enhanced with the inclusion of probiotic cultures and honey. Honey can be safely used in association with different probiotic cultures during yoghurt manufacture for augmenting functional properties of yoghurt to extend health benefits. Honey may not be equally a suitable matrix for all yoghurt cultures or probiotic cultures.
Research limitations/implications
Reviewed literature indicated that limited research on animal or human feeding trials with honey containing yoghurt has been done. Clinical trials with honey containing yoghurt are emerging prior to its marketing as functional food.
Originality/value
Application of honey as a functional additive during the manufacture of probiotic yoghurt is suggested to extend the functional properties of normal yoghurt.