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1 – 10 of over 1000Laiming Yu, Yaqin Fu and Yubing Dong
The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely…
Abstract
Purpose
The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely researched and rapidly developed biodegradable copolyester. In a tensile test, we found that the fractured PBAT samples had a heat-driven shape memory effect which piqued our interest, and it will lay a foundation for the application of PBAT in new fields (such as heat shrinkable film).
Design/methodology/approach
The shape memory effect of PBAT and the effect of the thermomechanical condition on its shape memory property were confirmed and systematically investigated by a thermal mechanical analyzer and tensile machine.
Findings
The results showed that the PBAT film had broad shape memory transform temperature and exhibited excellent thermomechanical stability and shape memory properties. The shape memory fixity ratio (Rf) of the PBAT films was increased with the prestrain temperature and prestrain, where the highest Rf exceeded 90%. The shape memory recovery ratio (Rr) of the PBAT films was increased with the shape memory recovery temperature and decreased with the prestrain value, and the highest Rr was almost 100%. Moreover, the PBAT films had high shape memory recovery stress which increased with the prestrain value and decreased with the prestrain temperature, and the highest shape memory recovery stress can reach 7.73 MPa.
Research limitations/implications
The results showed that PBAT had a broad shape memory transform temperature, exhibited excellent thermomechanical stability and shape memory performance, especially for the sample programmed at high temperature and had a larger prestrian, which will provide a reference for the design, processing and application of PBAT-based heat shrinkable film and smart materials.
Originality/value
This study confirmed and systematically investigated the shape memory effect of PBAT and the effect of the thermomechanical condition on the shape memory property of PBAT.
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Sai Vamsi Krishna Tataverthi and Srinivasa Rao Devisetty
The purpose of this study is to assess the influence of Al and Ag addition on thermal, mechanical and shape memory properties of Cu-Al-Ag alloy.
Abstract
Purpose
The purpose of this study is to assess the influence of Al and Ag addition on thermal, mechanical and shape memory properties of Cu-Al-Ag alloy.
Design/methodology/approach
The material is synthesized in a controlled atmosphere to minimize the reaction of alloying elements with the atmosphere. Cast samples were homogenized, then subjected to hot rolling and further betatized, followed by step quenching. Eight samples were chosen for study among which first four samples varied in Al content, and the next set of four samples varied in Ag composition.
Findings
The testing yielded a result that the increase in binary alloying element decreased transformation temperature range but increased entropy and elastic energy values. It also improved the shape memory effect and mechanical properties (UTS and hardness). An increase in ternary alloying element increased transformation temperature range, entropy and elastic energy values. The shape memory effect and mechanical properties are enhanced by the increase in ternary alloying element. The study revealed that compositional variation of Al should be limited to a range of 8 to 14 Wt.% and Ag from 2 to 8 Wt.%. Microstructural and diffraction studies identified the ß’1 martensite as a desirable phase for enhancing shape memory properties.
Originality/value
Numerous studies have been made in exploring the transformation temperature and phase formation for similar Cu-Al-Ag shape memory alloys, but their influence on shape memory effect was not extensively studied. In the present work, the influence of Al and Ag content on shape memory characteristics is carried out to increase the design choice for engineering applications of shape memory alloy. These materials exhibit mechanical and shape memory properties within operating ranges similar to other copper-based shape memory alloys.
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Wenjun Wang, Luting Shen, Yinsong Si, Islam MD Zahidul, Azim Abdullaev and Yubing Dong
Sodium alginate (Na-Alg) is a natural polysaccharide with a rich and renewable production that is widely used in the food, pharmaceutical and daily necessities industries, among…
Abstract
Purpose
Sodium alginate (Na-Alg) is a natural polysaccharide with a rich and renewable production that is widely used in the food, pharmaceutical and daily necessities industries, among other fields. The purpose of this study is to obtain a green and degradable shape memory material, calcium alginate (Ca-Alg) film was prepared and the mechanical properties, the shape memory effect of the film were investigated and confirmed.
Design/methodology/approach
The Ca-Alg films were prepared by Na-Alg, calcium chloride (CaCl2) solution, and flow extension method. Dissolve sodium alginate powder, remove bubbles, pour into petri dish, dry at 60°C, add calcium chloride solution cross-linking and finally dry naturally. The effect of CaCl2 solution concentration on the mechanical properties of the films were investigated and discussed by universal tensile tester. The shape memory behavior and degradation performance of thin films were verified and studied by the fold-deploy shape memory test and soil embedding method, respectively.
Findings
The Ca-Alg films exhibited good mechanical and shape memory properties, with a 72.2% shape memory fixity ratio and a 92.3% shape memory recovery ratio, respectively. For a period of 120 days, the film treated with a 6 wt% CaCl2 solution degraded at a rate of approximately 53%.
Research limitations/implications
Shape memory polymers (SMPs) as intelligent materials are an important research direction for the development of modern high-tech materials. On the other hand, plastic pollution is a major problem today; as a result, preparing green degradable SMPs is essential.
Originality/value
This study synthesized transparent and degradable shape memory Ca-Alg films using Na-Alg and CaCl2 solution and the flow extension method.
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Yajun Chen, Zehuan Sui and Juan Du
This paper aims to focus on the research progress of intelligent self-healing anti-corrosion coatings in the aviation field in the past few years. The paper provides certain…
Abstract
Purpose
This paper aims to focus on the research progress of intelligent self-healing anti-corrosion coatings in the aviation field in the past few years. The paper provides certain literature review supports and development direction suggestions for future research on intelligent self-healing coatings in aviation.
Design/methodology/approach
This mini-review uses a systematic literature review process to provide a comprehensive and up-to-date review of intelligent self-healing anti-corrosion coatings that have been researched and applied in the field of aviation in recent years. In total, 64 articles published in journals in this field in the last few years were analysed in this paper.
Findings
The authors conclude that the incorporation of multiple external stimulus-response mechanisms makes the coatings smarter in addition to their original self-healing corrosion protection function. In the future, further research is still needed in the research and development of new coating materials, the synergistic release of multiple self-healing mechanisms, coating preparation technology and corrosion monitoring technology.
Originality/value
To the best of the authors’ knowledge, this is one of the few systematic literature reviews on intelligent self-healing anti-corrosion coatings in aviation. The authors provide a comprehensive overview of the topical issues of such coatings and present their views and opinions by discussing the opportunities and challenges that self-healing coatings will face in future development.
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Fukang Yang, Wenjun Wang, Yongjie Yan and YuBing Dong
Polyethylene terephthalate (PET) as a fiber molding polymer is widely used in aerospace, electrical and electronic, clothing and other fields. The purpose of this study is to…
Abstract
Purpose
Polyethylene terephthalate (PET) as a fiber molding polymer is widely used in aerospace, electrical and electronic, clothing and other fields. The purpose of this study is to improve the thermal insulation performance of polyethylene terephthalate (PET), the SiO2 aerogel/PET composites slices and fibers were prepared, and the effects of the SiO2 aerogel on the morphology, structure, crystallization property and thermal conductivity of the SiO2 aerogel/PET composites slices and their fibers were systematically investigated.
Design/methodology/approach
The mass ratio of purified terephthalic acid and ethylene glycol was selected as 1:1.5, which was premixed with Sb2O3 and the corresponding mass of SiO2 aerogel, and SiO2 aerogel/PET composites were prepared by direct esterification and in-situ polymerization. The SiO2 aerogel/PET composite fibers were prepared by melt-spinning method.
Findings
The results showed that the SiO2 aerogel was uniformly dispersed in the PET matrix. The thermal insulation coefficient of PET was significantly reduced by the addition of SiO2 aerogel, and the thermal conductivity of the 1.0 Wt.% SiO2 aerogel/PET composites was reduced by 75.74 mW/(m · K) compared to the pure PET. The thermal conductivity of the 0.8 Wt.% SiO2 aerogel/PET composite fiber was reduced by 46.06% compared to the pure PET fiber. The crystallinity and flame-retardant coefficient of the SiO2 aerogel/PET composite fibers showed an increasing trend with the addition of SiO2 aerogel.
Research limitations/implications
The SiO2 aerogel/PET composite slices and their fibers have good thermal insulation properties and exhibit good potential for application in the field of thermal insulation, such as warm clothes. In today’s society where the energy crisis is becoming increasingly serious, improving the thermal insulation performance of PET to reduce energy loss will be of great significance to alleviate the energy crisis.
Originality/value
In this study, SiO2 aerogel/PET composite slices and their fibers were prepared by an in situ polymerization process, which solved the problem of difficult dispersion of nanoparticles in the matrix and the thermal conductivity of PET significantly reduced.
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Farid Salari, Paolo Bosetti and Vincenzo M. Sglavo
Particles bed binding by selective cement activation (SCA) method is a computer-aided manufacturing (CAM) technique used to produce cementitious elements. A computer-aided design…
Abstract
Purpose
Particles bed binding by selective cement activation (SCA) method is a computer-aided manufacturing (CAM) technique used to produce cementitious elements. A computer-aided design file is sliced to generate G-codes before printing. This paper aims to study the effect of key input parameters for slicer software on the final properties of printed products.
Design/methodology/approach
The one factor at a time (OFAT) methodology is used to investigate the impact of selected parameters on the final properties of printed specimens, and the causes for the variations in outcomes of each variable are discussed.
Findings
Finer aggregates can generate a more compact layer, resulting in a denser product with higher strength. Fluid pressure is directly determined by voxel rate (rV); however, high pressures enable better fluid penetration control for fortified products; for extreme rVs, residual voids in the interfaces between successive layers and single-line primitives impair mechanical strength. It was understood that printhead movement along the orientation of the parts in the powder bed improved the mechanical properties.
Originality/value
The design of experiment (DOE) method assesses the influence of process parameters on various input printing variables at the same time. As the resources are limited, a fractional factorial plan is carried out on a subset of a full factorial design; hence, providing physical interpretation behind changes in each factor is difficult. OFAT aids in analyzing the effect of a change in one factor on output while all other parameters are kept constant. The results assist engineers in properly considering the influence of variable variations for future DOE designs.
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Nivin Vincent and Franklin Robert John
This study aims to understand the current production scenario emphasizing the significance of green manufacturing in achieving economic and environmental sustainability goals to…
Abstract
Purpose
This study aims to understand the current production scenario emphasizing the significance of green manufacturing in achieving economic and environmental sustainability goals to fulfil future needs; to determine the viability of particular strategies and actions performed to increase the process efficiency of electrical discharge machining; and to uphold the values of sustainability in the nonconventional manufacturing sector and to identify future works in this regard.
Design/methodology/approach
A thorough analysis of numerous experimental studies and findings is conducted. This prominent nontraditional machining process’s potential machinability and sustainability challenges are discussed, along with the current research to alleviate them. The focus is placed on modifications to the dielectric fluid, choosing affordable substitutes and treating consumable tool electrodes.
Findings
Trans-esterified vegetable oils, which are biodegradable and can be used as a substitute for conventional dielectric fluids, provide pollution-free machining with enhanced surface finish and material removal rates. Modifying the dielectric fluid with specific nanomaterials could increase the machining rate and demonstrate a decrease in machining flaws such as micropores, globules and microcracks. Tool electrodes subjected to cryogenic treatment have shown reduced tool metal consumption and downtime for the setup.
Practical implications
The findings suggested eco-friendly machining techniques and optimized control settings that reduce energy consumption, lowering operating expenses and carbon footprints. Using eco-friendly dielectrics, including vegetable oils or biodegradable dielectric fluids, might lessen the adverse effects of the electrical discharge machine operations on the environment. Adopting sustainable practices might enhance a business’s reputation with the public, shareholders and clients because sustainability is becoming increasingly significant across various industries.
Originality/value
A detailed general review of green nontraditional electrical discharge machining process is provided, from high-quality indexed journals. The findings and results contemplated in this review paper can lead the research community to collectively apply it in sustainable techniques to enhance machinability and reduce environmental effects.
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Tseng-Lung Huang and Henry F.L. Chung
Drawing on embodied cognition theory, this study examined the impact of midair, gesture-based somatosensory augmented reality (AR) experience on consumer delight and stickiness…
Abstract
Purpose
Drawing on embodied cognition theory, this study examined the impact of midair, gesture-based somatosensory augmented reality (AR) experience on consumer delight and stickiness intention. The mediating effects of three psychological states for body schema (i.e. natural symbol sets, vivid memory and human touch) on the relationships between somatosensory AR and consumer delight/stickiness intention are determined. By filling gaps in the research, we hope to provide guidance on how to drive delightful somatosensory AR marketing.
Design/methodology/approach
Two experiments were conducted (Study 1 and Study 2) to test the research model and hypotheses. These experiments compared the effects of the “presence” (midair, gesture-based) and “absence” (mouse-based traditional website) conditions in somatosensory AR on consumer body schema and the creation of a delightful virtual shopping experience (i.e. consumer delight and stickiness intention).
Findings
The consumer delight and stickiness intention created in the presence condition was much higher than those in the absence condition. Consumers appeared to prefer engaging in a midair gesture-based somatosensory AR experience and exploring an augmented metaverse reality to interacting with a mouse-based traditional website. We also found that giving online consumers more somatosensory activities and kinesthetic experiences effectively inspired three psychological states of body schema in online consumers.
Originality/value
The results contribute to the AR experience and somatosensory marketing literature by revealing the role of natural symbol sets, vivid memory and the sense of human touch. This research breaks through the long-developed research paradigm on consumer delight, which has been limited to traditional entities and web contexts. We also extend embodied cognition theory to the study of somatosensory AR marketing.
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Tseng-Lung Huang, Henry F.L. Chung and Xiang Chen
The purpose of this study is to clarify the role of various levels of modality richness [text-visual, audiovisual and augmented reality interactive technology (ARIT)] on vivid…
Abstract
Purpose
The purpose of this study is to clarify the role of various levels of modality richness [text-visual, audiovisual and augmented reality interactive technology (ARIT)] on vivid memories (visual sensory detailed, emotionally intense, first-person perspective and coherent) and exploratory behavior. To clarify which modality richness online retailers use is more appropriate to create a virtual reality simulation experience to fill a significant gap in the sensory interactive marketing paradigm.
Design/methodology/approach
A task-based laboratory study was conducted to provide users with private try-on space. A total of 429 valid questionnaires were collected, and partial least squares path modeling was adopted to test hypotheses.
Findings
The results indicate that various levels of modality richness (text-visual, audiovisual and ARIT) positively affect vivid memories (visual sensory detailed, emotionally intense, first-person perspective and coherent), and vivid memories successfully induce exploratory behavior.
Practical implications
The study results could also help retailers and brands with clear guidance in designing and creating simulation experience services and choosing the best way to present products. With the results of this research, retailers will also be able to grasp better the critical points of introducing innovative technology into the service experience and then create the benefits of digital economic growth.
Originality/value
Exploring which digital interactive technology online retailers use is more appropriate to create a virtual reality shopping experience to fill a significant gap in the sensory interactive marketing paradigm. Exploring the antecedents of vivid memories in a digital sensory interactive experience contributes to the body schema literature and the script theory. We draw from construal level theory (CLT) to clarify the impact of various levels of modality richness on driving the difference in sensory simulation schema to break through the limited findings of previous studies, namely using CLT to interpret psychological distance.
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Pratibha Maan and Dinesh Kumar Srivastava
The study aims to define the term “generation” by proposing an integrated design based on age-period-cohort effects and by proposing an Indian generational cohort framework…
Abstract
Purpose
The study aims to define the term “generation” by proposing an integrated design based on age-period-cohort effects and by proposing an Indian generational cohort framework categorizing Indian generational cohorts into four categories, namely, Baby Boomers, GenX, GenY, and GenZ. The study further aimed to capture the existing generational differences between GenY and GenZ cohorts in the Indian teams on team climate, transactive memory system, and team leader humility.
Design/methodology/approach
For the first two objectives a literature review methodology along with the author's proposition was adopted. An integrated design was proposed by reviewing the relevant sociological literature to define generations. Thereafter, an Indian cohort framework was proposed categorizing them into four groups Baby Boomers, GenX, GenY, and GenZ. Following that, for the last objective, i.e. to identify the differences between cohorts, empirical data were collected by a structured questionnaire that was disseminated to GenY and GenZ Indian working professionals. A total of 229 responses were used for observing the differences or similarities between GenY and GenZ cohorts on the study variables by employing an independent samples t-test.
Findings
The study proposed an integrated design (age, period, and cohort effect). Following that, an Indian generational cohort's framework has been outlined categorizing Indian cohorts based on their birth years, age groups, developmental stages, formative years, major Indian historical events, and various characteristics possessed by them. Moreover, the empirical findings support the existing generational disparities and depict that GenZ holds a higher inclination towards transactive memory systems and team climate whereas GenY holds more inclination toward leader humility.
Practical implications
The study put forth its contribution to research scholars by categorizing Indian generational cohorts in a rationalized manner based on an integrated design (age-period-cohort) effect. The study would further assist concerned authorities and managers in formulating HR policies to deal with the underlying generational differences highlighted by the study.
Originality/value
As there lies a paucity of generational frameworks in the Indian context, this study is the first attempt in this direction which categorizes Indian generational cohorts based on a unique integrated design including age-period-cohort effects. In addition, the study also investigated these cohorts in Indian organizations to observe the existing variations.
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