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1 – 10 of 21Hamaid Mahmood Khan, Saad Waqar and Ebubekir Koç
The current investigation aims at observing the influence of the cooling channel on the thermal and residual stress behavior of the selective laser melting (SLM)316L uni-layer…
Abstract
Purpose
The current investigation aims at observing the influence of the cooling channel on the thermal and residual stress behavior of the selective laser melting (SLM)316L uni-layer thermo-mechanical model.
Design/methodology/approach
On a thermo-mechanical model with a cooling channel, the effect of scanning direction, parallel and perpendicular and scan spacing was simulated. The effect of underlying solid and powder bases was evaluated on residual stress profile and thermal variables at various locations.
Findings
The high heat dissipation of solid base due to high cooling rates and steep thermal gradients can reciprocate with smaller melt pool temperature and melt pool size. Given the same scan spacing, residual stresses were found lower when laser scanning was perpendicular to the cooling channel. Moreover, large scan spacing was found to increase residual stresses.
Originality/value
Cooling channels are increasingly being used in additive manufacturing; however, their effect on the residual stress behavior of the SLM component is not extensively studied. This research can serve as a foundation for further inquiries into the impact of base material design such as cooling channels on manufactured components using SLM.
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Mustafa Kuntoğlu, Emin Salur, Munish Kumar Gupta, Saad Waqar, Natalia Szczotkarz, Govind Vashishtha, Mehmet Erdi Korkmaz, Grzegorz M. Krolczyk, Abdullah Aslan and Rüstem Binali
Additive manufacturing became the most popular method as it enables the production of light-weight and high-density parts in effective way. Selective laser melting (SLM) is…
Abstract
Purpose
Additive manufacturing became the most popular method as it enables the production of light-weight and high-density parts in effective way. Selective laser melting (SLM) is preferred by means of producing a component with good surface quality and near-net shape even if it has complex form. Titanium alloys have been extensively used in engineering covering a variety of sectors such as aeronautical, chemical, automotive and defense industry with its unique material properties. Therefore, the purpose of this review is to study the tribological behavior and surface integrity that reflects the thermal and mechanical performances of the fabricated parts.
Design/methodology/approach
This paper is focused on the tribological and surface integrity aspects of SLM-produced titanium alloy components. It is aimed to outline the effect of SLM process parameters on tribology and surface integrity first. Then, thermal, thermal heat, thermomechanical and postprocessing surface treatments such as peening, surface modification and coatings are highlighted in the light of literature review.
Findings
This work studied the effects of particle characteristics (e.g. size, shape, distributions, flowability and morphology) on tribological performance according to an extensive literature survey.
Originality/value
This study addresses this blind spot in existing industrial-academic knowledge and goals to determine the impact of SLM process parameters, posttreatments (especially peening operations) and particle characteristics on the SLMed Ti-based alloys, which are increasingly used in biomedical applications as well as other many applications ranging from automobile, aero, aviation, maritime, etc. This review paper is created with the intention of providing deep investigation on the important material characteristics of titanium alloy-based components, which can be useful for the several engineering sectors.
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Mustafa Kuntoğlu, Emin Salur, Munish Kumar Gupta, Saad Waqar, Natalia Szczotkarz, Govind Vashishtha, Mehmet Erdi Korkmaz and Grzegorz M. Krolczyk
The nickel-based alloys Inconel 625 and Inconel 718 stand out due to their high strength and corrosion resistance in important industries like aerospace, aviation and automotive…
Abstract
Purpose
The nickel-based alloys Inconel 625 and Inconel 718 stand out due to their high strength and corrosion resistance in important industries like aerospace, aviation and automotive. Even though they are widely used, current techniques of producing materials that are difficult to cut pose several problems from a financial, ecological and even health perspective. To handle these problems and acquire improved mechanical and structural qualities, laser powder bed fusion (LPBF) has been widely used as one of the most essential additive manufacturing techniques. The purpose of this article is to focus on the state of the art on LPBF parts of Inconel 625 and Inconel 718 for microstructure, mechanical behavior and postprocessing.
Design/methodology/approach
The mechanical behavior of LPBF-fabricated Inconel is described, including hardness, surface morphology and wear, as well as the influence of fabrication orientation on surface quality, biocompatibility and resultant mechanical properties, particularly tensile strength, fatigue performance and tribological behaviors.
Findings
The postprocessing techniques such as thermal treatments, polishing techniques for surface enhancement, mechanical and laser-induced peening and physical operations are summarized.
Originality/value
The highlighted topic presents the critical aspects of the advantages and challenges of the LPBF parts produced by Inconel 718 and 625, which can be a guideline for manufacturers and academia in practical applications.
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Saad Waqar, Jiangwei Liu, Qidong Sun, Kai Guo and Jie Sun
This paper aims to investigate the influence of different post-annealing cooling conditions, i.e. furnace cooling (heat treatment (HT) 1 – slow cooling) and air cooling (HT 2 …
Abstract
Purpose
This paper aims to investigate the influence of different post-annealing cooling conditions, i.e. furnace cooling (heat treatment (HT) 1 – slow cooling) and air cooling (HT 2 – fast cooling), on the microstructure and mechanical properties of selective laser melting (SLM) built austenitic 316L stainless steel (SS).
Design/methodology/approach
Three sets of 316L SS samples were fabricated using a machine standard scanning strategy. Each set consists of three tensile samples and a cubic sample for microstructural investigations. Two sets were subsequently subjected to annealing HT with different cooling conditions, i.e. HT 1 and HT 2, whereas one set was used in the as-built (AB) condition. The standard metallographic techniques of X-ray diffraction, scanning electron microscopy and electron back-scattered diffraction were used to investigate the microstructural variations induced by different cooling conditions. The resultant changes in mechanical properties were also investigated.
Findings
The phase change of SLM fabricated 316L was observed to be independent of the investigated cooling conditions and all samples consist of austenite phase only. Both HT 1 and HT 2 lead to dissolved characteristic melt pools of SLM. Noticeable increase in grain size of HT 1 and HT 2 samples was also observed. Compared with AB samples, the grain size of HT 1 and HT 2 was increased by 12.5% and 50%, respectively. A decreased hardness and strength, along with an increased ductility was also observed for HT 2 samples compared with HT 1 and AB samples.
Originality/value
From previous studies, it has been noticed that most investigations on HT of SLM fabricated 316L were mainly focused on the HT temperature or holding time. However, the post-HT cooling rate is also an equally important factor in deciding the microstructure and mechanical properties of heat-treated components. Therefore, this paper investigates the influence of different post-annealing cooling conditions on microstructure and mechanical properties of SLM fabricated 316L components. This study provides a foundation for considering the post-HT cooling rate as an influential parameter that controls the properties of heat-treated SLM components.
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Hammad Bin Azam Hashmi, Chengli Shu and Syed Waqar Haider
Although the store environment-impulse buying nexus is well documented, the influence of consumer motivations on this nexus is still underexplored. Consequently, this paper aims…
Abstract
Purpose
Although the store environment-impulse buying nexus is well documented, the influence of consumer motivations on this nexus is still underexplored. Consequently, this paper aims at explaining the mediating effect of emotional states and the moderating effect of hedonic shopping motives on the relationship between store atmospherics and impulse buying behavior.
Design/methodology/approach
Primary data from 437 customers were generated through a questionnaire developed for this study. Respondents were accessed using mall-intercept technique. Structural equation modeling (SEM) was done to empirically estimate the model.
Findings
Results indicate that pleasure and shopping enjoyment mediate the effect of store atmospherics on the impulse purchase behavior. The findings also show that hedonic shopping motives moderate the relationship between the store atmospherics and impulse purchase.
Originality/value
This study contributes by introducing the moderating role played by the hedonic shopping motives on the relationship between store atmospherics and impulse purchase. In addition, it introduces that shopping enjoyment and pleasure mediate the effect of perceived store atmospherics on impulse purchase.
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Ahsan Waqar, Idris Othman and Muhammad Shoaib Mansoor
The primary objective of this study is to examine the effects of integrating human-centric technology on the overall effectiveness of sustainable building practises. This study…
Abstract
Purpose
The primary objective of this study is to examine the effects of integrating human-centric technology on the overall effectiveness of sustainable building practises. This study intends to address the knowledge gap regarding the influence of human-centered factors on the adoption of technology in the construction industry. Additionally, it wants to establish a strong correlation between the integration of technology and the promotion of sustainability.
Design/methodology/approach
This research utilizes Partial Least Square Equation Modeling (SEM) as a comprehensive approach to analyze the intricate interrelationships within the building sector. This study examines a range of aspects, including “Change Management,” “Evaluation and Optimization,” “Integration and Coordination,” “Long-Term Planning,” “Safety and Compliance,” and “Training and User Engagement,” in order to evaluate their impact on the adoption of technology and the achievement of sustainable building outcomes.
Findings
The study reveals a robust and affirmative correlation between the use of human-centric technology and the attainment of success in the realm of sustainable building. The text elucidates the primary factors that influence the adoption of technology and underscores the need of adopting a comprehensive strategy that encompasses change management, adherence to safety standards, and optimization of resources.
Originality/value
This study contributes novelty by placing emphasis on the human-centric dimensions of technology adoption within the context of sustainable building. The results of this research provide a valuable contribution to the ongoing development of sustainable building practises and the adoption of new technologies in this sector.
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Sehrish Huma, Waqar Ahmed and Arsalan Najmi
In the era of market turbulence, sourcing specialists consistently face challenges to keep the availability of the material efficiently and effectively without any disruption…
Abstract
Purpose
In the era of market turbulence, sourcing specialists consistently face challenges to keep the availability of the material efficiently and effectively without any disruption. Sourcing strategies and planning have a huge impact on procurement performance. The purpose of this paper is to examine the relationships among different sourcing strategies and supply risk management and performance and additionally, the role of procurement practices in different strategic settings.
Design/methodology/approach
This is empirical research that collected data gathered from 223 procurement specialists working in various manufacturing firms through a structured questionnaire. Valid data is then analyzed through the structure equation modeling technique for hypotheses testing.
Findings
The findings of this study reveal that supplier development is a partial complementary mediator between multiple supplier strategy and supply-side risk management. While in a volatile business environment, strategic supplier strategy has a significant negative impact on supply-side risk management, and in this case supplier development acts as a competing partial mediator between the two. Contract management has resulted in an important mechanism to be deployed in a strategic sourcing strategy. It is also shown that supplier risk management is also associated with improved supply management performance.
Practical implications
This paper establishes an explanation of theoretical and practical understanding of sourcing strategies and empirically shows that supplier development is the appropriate mechanism to deal with supply-side risk management, which in turn positively impacts on supplier management performance.
Originality/value
This study contributes to supply chain risk management literature, especially in the context of strategic risk management and explains how a strategic decision can impact supply risk management. This provides a piece of empirical evidence regarding the use of well-established procurement practices to improve supply performance.
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Muhammad Zeeshan Rafique, Mohd Nizam Ab Rahman, Nizaroyani Saibani, Norhana Arsad and Waqar Saadat
Lean manufacturing is one of the leading paradigms for fast and proficient manufacturing but its proper implementation is a foremost task due to certain barriers affecting lean…
Abstract
Purpose
Lean manufacturing is one of the leading paradigms for fast and proficient manufacturing but its proper implementation is a foremost task due to certain barriers affecting lean and can be handled when utilized with RFID technology. With this aspect in view, the purpose of this paper is to enlighten and present a thorough literature study that can show how RFID-based lean manufacturing is helpful for handling barriers affecting lean manufacturing in light of previous literature available.
Design/methodology/approach
In order to achieve this purpose a systematic literature review is conducted to justify the impacts of RFID technology for handling barriers. The aim of this systematic literature review is to initially find the barriers affecting lean implementation and then to explain the properties of RFID-based lean manufacturing which are highly feasible to handle detected barriers.
Findings
An interrelation is generated in this study which provides a clear indication that the properties of RFID carry significant effects to handle detected barriers in the operational, managerial and financial regime of manufacturing companies. The detected barriers that affect lean implementation are company’s cultures, top management commitment, poor employee administration, lack of finances, unbalanced inventory control, unstable customer handling and longer lead times. The properties of RFID-based lean manufacturing like operational visibility, inventory control, production control, minimized lead times and the real-time data information (to facilitate top management and employees on shop floor) are extremely helpful to control these barriers.
Originality/value
The originality of this study is the provision of clarity provided to both academicians and practitioners by citing and utilizing previous research studies which undoubtedly indicates positive impacts of RFID on lean implementation.
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Javaria Waqar and Osman Sadiq Paracha
This study aims to examine the key antecedents influencing the private firm’s intention to adopt big data analytics (BDA) in developing economies. To do so, the study follows the…
Abstract
Purpose
This study aims to examine the key antecedents influencing the private firm’s intention to adopt big data analytics (BDA) in developing economies. To do so, the study follows the sequential explanatory approach.
Design/methodology/approach
To test the hypothesized model that draws on the technology–organization–environment (TOE) framework paired with the diffusion of innovation (DOI) theory, a purposive sampling technique was applied to gather data from 156 IT and management domain experts from the private firms that intend to adopt BDA and operate in Pakistan’s service industry, including telecommunication, information technology, agriculture, and e-commerce. The data were analysed using the partial least squares structural equations modelling (PLS-SEM) technique and complemented with qualitative analysis of 10 semi-structured interviews in NVIVO 12 based on grounded theory.
Findings
The empirical findings revealed that the two constructs – perceived benefits and top management support – are the powerful drivers of a firm’s intention to adopt BDA in the private sector, whereas IT infrastructure, data quality, technological complexity and financial readiness, along with the moderators, BDA adoption of competitors and government policy and regulation, do not significantly influence the intention. In addition, the qualitative analysis validates and further complements the SEM findings.
Originality/value
Unlike the previous studies on technology adoption, this study proposed a unique research model with contextualized indicators to measure the constructs relevant to private firms, based on the TOE framework and DOI theory, to investigate the causal relationship between drivers and intention. Furthermore, the findings of PLS-SEM were complemented by qualitative analysis to validate the causation. The findings of this study have both theoretical and practical implications.
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