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High temperature gradient induces high residual stress, producing an important effect on the part manufacturing during laser powder bed fusion (LPBF). The purpose of this study is to investigate the effect of the molten pool mode on the thermal stress of Ti-6Al-4V alloy during different deposition processes.

A coupled thermal-mechanical finite element model was built. The developed model was validated by comparing the numerical results with the experimental data in the maximum molten pool temperature, the molten pool dimension and the residual stress described in the previous work.

For the single-track process, the keyhole mode caused an increase in both the maximum stress and the high-stress area compared with the conduction mode. For the multitrack process, a lower tensile stress around the scanning track and a higher compressive stress below the scanning track were found in the keyhole mode. For the multilayer process, the stress along the scanning direction at the middle of the part changed from tensile stress to compressive stress with the increase in the deposition layer number. As the powder layer number increased, the stress along the scanning direction near the top surface of the part decreased while the stress along the deposition direction obviously increased, indicating that the stress along the deposition direction became the dominant stress. The keyhole mode can reduce the residual stress near the top of the part, and the conduction mode was more likely to produce a low residual stress near the bottom of the part.

The results provide a systematic understanding of thermal stress during the LPBF process.

The purpose of this study is to investigate the effect of the strut size and tilt angle on the densification behavior, surface roughness and dimensional accuracy of the selective laser melting AlSi10Mg lattice structure was investigated in this study. In this study, the characteristics such as the density, up-skin and down-skin roughness and dimensional accuracy of selective laser melting forming technology manufacturing (SLMed) AlSi10Mg cellular lattice structure were carried. This work reveals the effect of the strut size and tilt angle on the geometric characteristics of SLMed AlSi10Mg and is benefit for controlling the forming performance of the SLMed cellular lattice structure.

Based on AlSi10Mg powder, the influence of the tilt angle changed from 10° to 45° with an increment of 5° were investigated, the influence of the strut size was varied from 0.4 mm to 1.2 mm with an increment of 0.2 mm were investigated. The characteristics such as the density, up-skin and down-skin roughness, dimensional accuracy and mechanical properties of SLM-ed AlSi10Mg cellular lattice structure was carried.

Greater than 99% relative density can be achieved for different strut size when optimal process parameters are used. In the optimized process interval, the struts with a tilt angle of 10° can still be formed well, which is higher than the design limit of the inclined angle given in the related literature. The tilt angle has a significant effect on the surface roughness of the strut. The microhardness reached to 157 ± 3 HV, and the maximum compressive strength was 58.86 MPa, with the optimal process parameters.

In this study, the characteristics such as the density, up-skin and down-skin roughness and dimensional accuracy of SLMed AlSi10Mg cellular lattice structure were carried. With the optimal geometric parameters, the authors tested microhardness and compressive strength of the cellular lattice structure. The results of this study provide theoretical and experimental basis for the realization of high-quality manufacturing and optimization design of aluminum alloy cellular lattice structure, which will meet more diversified industrial needs.

High residual stress caused by the high temperature gradient brings undesired effects such as shrinkage and cracking in selective laser melting (SLM). The purpose of this study is to predict the residual stress distribution and the effect of process parameters on the residual stress of selective laser melted (SLMed) Inconel 718 thin-walled part.

A three-dimensional (3D) indirect sequentially coupled thermal–mechanical finite element model was developed to predict the residual stress distribution of SLMed Inconel 718 thin-walled part. The material properties dependent on temperature were taken into account in both thermal and mechanical analyses, and the thermal elastic–plastic behavior of the material was also considered.

The residual stress changes from compressive stress to tensile stress along the deposition direction, and the residual stress increases with the deposition height. The maximum stress occurs at both ends of the interface between the part and substrate, while the second largest stress occurs near the top center of the part. The residual stress increases with the laser power, with the maximum equivalent stress increasing by 21.79 per cent as the laser power increases from 250 to 450 W. The residual stress decreases with an increase in scan speed with a reduction in the maximum equivalent stress of 13.67 per cent, as the scan speed increases from 500 to 1,000 mm/s. The residual stress decreases with an increase in layer thickness, and the maximum equivalent stress reduces by 33.12 per cent as the layer thickness increases from 20 to 60µm.

The residual stress distribution and effect of process parameters on the residual stress of SLMed Inconel 718 thin-walled part are investigated in detail. This study provides a better understanding of the residual stress in SLM and constructive guidance for process parameters optimization.

This study aims to explore the dynamic interplay between consumer innovativeness and willingness to pay a green premium (WPGP), moderated by the information frames of social norms. Using a cybernetic framework, we examine how consumer traits and the presentation of social norms (including descriptive and injunctive norms) influence green consumption.

This study conducts a between-subjects survey experiment and collects a sample from 535 Chinese consumers to examine the hypothesis.

Our findings reveal that different dimensions of consumer innovativeness – hedonic, social, functional and cognitive – affect WPGP in varied ways. Importantly, the effect of functionally motivated consumer innovativeness (fMCI) is significantly moderated by how social norms are framed. We also find that negatively framed norms about the number of people do not consume green products and consequences of not engaging in green behaviours are generally more effective than positively framed norms in influencing WPGP, though the effect is slight.

The study employs a comprehensive experimental design with a Chinese sample to test these relationships, contributing novel insights into the marketing strategies and policy formulations necessary to enhance green consumption. By integrating theories of normative social behaviour and bounded rationality, our research not only deepens the understanding of consumer behaviour in environmental contexts but also offers practical implications for fostering more sustainable consumption patterns.

By market capitalisation, Bitcoin, which debuted in 2009, is the biggest cryptocurrency globally. A decentralised ledger system called blockchain is used in the creation, distribution, trading, and storage of Bitcoin, with the original goal being to address the shortcomings of fiat currency. This chapter highlights potential dangers and legal concerns when Bitcoin interacts with the actual economy and the traditional financial system. Besides, the details also discuss the platform’s design principles and attributes for a non-technical readership. When assessing its transactional potential, some recognise its potential for speculation, while others are doubtful of its admirable intent. The write-up also explores the potential of the adoption of cryptocurrencies in Southeast Asia due to the vast adoption of Bitcoins in countries such as Vietnam and the Philippines following the establishment of cryptocurrency technology and e-commerce. In addition, rankings of the cryptocurrency and legal stance from each country in Southeast Asia were exhibited as the solid foundation of cryptocurrencies existent for transaction purposes. The rise of central bank digital currencies (CBDC) and the future directions of Bitcoins were also highlighted in this write-up to spur the debate on whether cryptocurrency remains a fad of sensation or is legalised as the medium of exchange in an ever-growing digital world of commerce.