A Review on Energy Consumption and Efficiency of Selective Laser Melting Considering Support: Advances and Prospects

Qingyang Wang,Mengdi Gao,Qiang Li,Conghu Liu,Lei Li,Xinyu Li,Zhifeng Liu 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.11 No.1

Selective laser melting (SLM) exhibits excellent manufacturing accuracy and forming ability. However, the laser beam layering process is characterized by high specific energy consumption, long manufacturing cycle, and low energy efficiency. The use of supports increases the SLM building quality and eliminates defects caused by thermal and residual stresses; however, an improper support structural design increases the process energy consumption for manufactured parts. To control energy consumption and building quality during SLM, this study first discusses the main challenges related to energy saving and improving the building quality by performing an energy consumption analysis, process energy consumption optimization, and supporting structure optimization. The obtained results reveal that it is difficult to achieve high building quality only by controlling the process parameters and energy consumption by the SLM equipment. Next, the effect of supporting structures on the process energy consumption is examined to enable the construction of an SLM energy consumption model that considers the presence of supports. Finally, the effect of supports on the building quality is elucidated by studying the influence of supporting structures on thermal and residual stresses. By identifying the most energy-efficient support, the process energy efficiency and building quality may be simultaneously optimized. The proposed method represents a new approach to reducing energy consumption and improving the building quality during SLM. This study establishes a theoretical foundation for the subsequent industrial applications, providing a thorough literature review and describing the existing challenges in the SLM manufacturing field.

Research Trend of Creatine in Sport Using Social Network Analysis

( Yuan Wang ),( Kyungsik Kim ),( Wang Songjia ),( Ding Pan ),( Shao Qingyang ) 한국융합과학회 2022 한국융합과학회 국제학술대회자료집 Vol.2022 No.0

Since Michel Eugène Chevreul(1786-1889) firstly discovered Creatine in skeletal muscle in 1832[(Volek JS et al., 2012), Research on creatine has caught scholars' attention. Research results showed that Creatine was consumed in the diet and synthesized in the body and is widely utilized as an ergogenic aid for strength and performance gains(Wax B et al.,2021). In addition, a large body of compelling evidence demonstrated high-intensity exercise capacity and lean body mass would be improved by creatine supplementation(Cooper R et al.,2012).When used appropriately, creatine has very few adverse effects and has repeatedly proven to be safe for clinical use with similar beneficial applications across all age groups. In addition, Creatine supplementation has always been considered as a feasible way to treat muscular, neuromuscular or neuromuscular diseases. Including the treatment of arthritis, chronic congestive heart failure, disuse atrophy, circular atrophy, muscle phosphorylase deficiency, Huntington's disease, diversified neuromuscular diseases, mitochondrial diseases, muscular dystrophy and neuroprotection, B. Willer(2000) analyzed effects of creatine supplementation on muscle weakness in patients with rheumatoid arthritis, results of which showed that creatine may be beneficial to neuromuscular disorders. Also, M. Flint(1999 )’ research results indicated that Creatine was twice as effective as the current prescription drug riluzole in prolonging the liver life of rats with amyotrophic lateral sclerosis, which may be on account that available energy of injured nerve cells increased and chemical pathways causing cell death are blocked. Although many qualitative studies on creatine have been conducted, few studies on quantitative analysis of creatine were found. Therefore, three questions arouse the author's thinking as following, How is Research Trend of Creatine in Sport? What are hot topics on creatine research in recent years? In order to respond to these questions, it is necessary to analyze the changes in Creatine research over past years. Recently, social network analysis, which focuses on analyzing the degree centrality and betweenness centrality of keywords in a social network composed of core keywords, has been widely utilized in various research fields to identify research trends and assess sub-research fields. Researchers describe that the research trends can bee derived in a given field by observing the changes of core keywords in networks(Kim & Yim, 2017). In this paper, centrality and frequency changes of top keywords on Creatine by periods were conducted to identify research trends and assess detailed study areas. Methods In this study, detailed bibliographic information of 513 articles on Creatine was collected through searching the Web of Science. The bibliographic information includes journal title, article title, authors, abstract, keyword, and year of publication. To analyze the trends of Yoga therapy by specific periods, we divided the analyzed period into four parts (2000-2005, 2006-2010, 2011-2015, 2016-2020). When identifying research trends using social network analysis, the main element used was the abstract of articles, with the keywords in abstracts being extracted through textmining. To identify research trends, centralities and cohesion group analysis were performed using python and Netminer. First, degree centrality analysis and betweenness analysis were performed to identify keywords with influence within quantified abstract data to identify the development trends of Yoga therapy research. Second, cohesion group analysis was conducted to identify detailed sub-research areas within the network (Kim, 2018;Kim et al., 2020). Findings and applications The findings for the quantitative abstract data and visual network analyses are as follows. By counting, combining, and analyzing the keywords in Creatine research across the four different analyzed periods. The analysis results are as follows, degree centrality of top keywords, such as supplementation, effect, muscle, exercise, increase, placebo was high in four periods, which implied that the similar hot topics on effect of Creatine as supplementation on muscle in the four periods. Maybe the difference between Creatine and placebo during exercise also was the top topics during the four periods. Besides, keywords with high degree centrality also showed a high tendency in betweenness centrality. By contrary, compared the keywords of 4 periods, Differences can be noticed in research topics involving period, man and weight during 2006 and 2010y, and during 2016 and 2020y, keywords ck, player, supplement, serum and measure were covered, which indicated that new topics on ck, player, supplement, serum and measure were conducted, but the other two periods of research didn’t involve. In addition, four specific areas centered on creatine and CK, Creatine and effect, creatine and placebo effect, and Creatine and performance, were derived through cohesion group analysis. o it can be said that the results of keyword network analysis clearly show the sub-research fields of Creantine, which allow future researchers to make more well-informed decisions as to which detailed study areas to focus on. On the other hand, the overall research trend of Yoga therapy is confirmed through keyword network analysis, which will play a supplementary role in the further sub-research on Creatine.

Si–Ge alloys in C2/c phase with tunable direct band gaps: A comprehensive study

Qingyang Fan,Huiqin Wang,Wenzhu Zhang,Mingfei Wei,Yanxing Song,Wei Zhang,Sining Yun 한국물리학회 2019 Current Applied Physics Vol.19 No.12

Si–Ge alloys are a new type of semiconductor material that are of great significance for the development of microelectronic technology, especially in the photoelectricity industry and for thermoelectric conversion in high temperature applications (> 700 K). In the present work, a novel Ge allotrope in the C2/c phase with band gap of 1.102 eV was firstly proposed, which is suitable for the absorption of sunlight. C2/c-Ge are mechanically, dynamically and thermodynamically stable. A series of Si24-xGex alloys (x=0, 8, 16, 24) in the C2/c phase with band gaps of 1.10–1.50 eV are predicted by ab initio calculations at ambient conditions. The Si24-xGex alloys (x=0, 8, 16, 24) in C2/c phase have better absorption ability than that of the Si in diamond, hP12 and oC12 phases. The Si24-xGex alloys in the C2/c phase have the strong absorption in the visible, which have a great impact on the new-generation photovoltaic applications.

Experimental Investigation of Crack PropagationMechanism and Load-bearing Characteristics for Anti-slide Pile

Qingyang Ren,Feifei Wang,Xiaofeng Lin,Bin Chen,Xiangwei Zhang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.6

Reinforced concrete anti-slide pile is a typical anti-slide installation under horizontal load. Its stress is essentially the cantilever beam working under the combined action of bending moment and shear force. In the process of loading, concrete is accompanied by the generation and expansion of different forms of cracks. In order to reveal the bearing characteristics and crack propagation law of anti-slide pile, the 1:10 scale model of the anti-slide pile in Majiagou landslide treatment project was taken as the object. The mechanical mechanisms of three kinds of the anti-slide piles with different pile lengths were studied. The bending moment and deformation law of three anti-slide piles were obtained. The results show that the pile is easy to crack in the range of 0.5 m above and below the sliding surface. With the increase of cantilever length, the bending moment increases. The development of the maximum crack length and width presents the crack initiation stage, stable stage, and failure mutation stage. Through the monitoring of the length and width of the crack and the judgment of its stage, the working state of the pile can be obtained. The results can provide reference for the optimal design of anti-slide pile in landslide treatment engineering.

Influence of raw material grain composition on the properties of fused silica ceramics

Qingtao Wang,Sen Li,Huaqin Yu,Fengzhi Li,Huijun Xu,Haibo Qiao,Juncheng Liu,Qingyang Du 한양대학교 세라믹연구소 2017 Journal of Ceramic Processing Research Vol.18 No.8

Fused silica ceramics were prepared by slip casting method with various particle sizes (d50 ≈ 2.31 μm, 19.79 μm, and 71.46 μm)from three types of fused silica powder. The influence of raw material grain composition on the viscosity of slurry, bulk density,porosity, water absorption, and flexural strength of the fused silica ceramics was investigated. The slurry viscosity wasmeasured by an XND-1 viscometer. The bulk density, porosity, and water absorption of the sintered samples were obtainedby the Archimedes method. The flexural strength was measured by a three-point bending test. The phase composition andmicrostructure of the samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Theresults show that when the grain composition was 5 : 3 : 2, slurry viscosity was 150.79 mPa·s with solid content of 75%, thefused silica ceramic particles were packed most tightly and demonstrate bulk density of 2.02 g/cm3, porosity of 6.99%, waterabsorption of 3.47%, and flexural strength of 51.27 MPa.

Performance assessment and structural design of the atmospheric cutterhead of slurry shield machine

Feixiang Liu,Qingyang Wang,Zhiyong Ji,Laikuang Lin 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.11

The atmospheric cutterhead is a new type of cutterhead with high technical difficulty. Compared with the conventional cutterhead, the spatial structure of the atmospheric cutterhead is more complicated, and a mature design theory has not yet been formed. This paper presents an atmospheric cutterhead design method for slurry shield machines. The method was divided into three steps: (i) design load analysis; (ii) multiobjective topology optimization; and (iii) evaluation and selection of cutterhead structures. Based on topology optimization theory, four types of cutterhead structures with different numbers of radial arms are obtained. The performance of the cutterhead was evaluated by stress, deformation, vibration mode, opening situation and space complexity, and the five-radial arm cutterhead was determined to be the best solution. Analysing the actual tunnelling parameter data shows good engineering adaptability. This paper provides a reference for the optimal design of the atmospheric cutterhead of slurry shield machine.

Energy Efficiency and Dynamic Analysis of a Novel Hydraulic System with Double Actuator

Mengdi Gao,Lei Li,Qingyang Wang,Conghu Liu 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.7 No.3

At present, increased attention has been given to energy effi ciency promotion and energy saving of manufacturing equipment and systems. Hydraulic system is widely used in engineering machinery industries; however, the high energy consumption and low energy effi ciency of which limit its development and application. On the basis of previous research on hydraulic system, an energy-effi cient hydraulic system with double actuator is proposed in this study. This hydraulic system can reduce the energy consumption by reusing the potential energy loss of the system. In this novel hydraulic system, the chambers of two actuators are connected with rod by pipes and valves. During the operating processes, the falling operation of one cylinder and the returning operation of the other are synchronized. That is, one actuator remains at the top point performing the demanded operation, whereas the other one remains at the bottom performing the corresponding operation. System models are developed to address the energy consumption and dynamic performance of the proposed hydraulic system. This hydraulic system is applied into a press to study its energy-saving mechanism and dynamic performance during transient under various working conditions. On the basis of the simulation and experimental results, energy and production effi ciency are compared and discussed. Results show that in comparison with the energy and time consumption of the original 630 kN hydraulic press, the energy-saving potential has reached 17.34%, and the production effi ciency can be improved by 18.85%.

Integration of Additive Manufacturing in Casting: Advances, Challenges, and Prospects

Mengdi Gao,Lei Li,Qingyang Wang,Zhilin Ma,Xinyu Li,Zhifeng Liu 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.1

Additive manufacturing (AM) is a novel manufacturing technology that can create highly customized products with more complex geometries than traditional techniques. Despite its significant advantages, including the freedom of design, mass customization, and ability to produce complex structures, AM consumes a large amount of energy and incurs high costs. In addition, AM suffers from long production cycles and low production efficiency in the large-scale manufacturing of metal structures. This study offers a review of the existing literature focused on metal AM technology. To avoid the shortcomings of AM and highlight its bene fits, which are widely used for manufacturing in combination with casting. The current combination application of AM and casting is reviewed to provide solutions to the problem of manufacturing large metal components from the perspective of the use of different AM technology and quality control in casting. However, such integration is insufficient for producing large castings with complex shapes, structures, or multiple features. Therefore, a novel method for integrating AM into casting to enable the manufacture of large scale metal parts with complex shapes is introduced as a topic for possible future research. This method divides complex castings with multiple features into an AM processing part and the casting substrate. The complex features were processed by AM on the fabricated casting substrate. This study provides a review of the application of AM into casting and presents a novel idea for the integration application of AM and other processes. This promising method has significant value for future study.

Analysis and Optimization of Energy Consumption for Multi-part Printing Using Selective Laser Melting and Considering the Support Structure

Zhilin Ma,Mengdi Gao,Kai Guo,Qingyang Wang,Lei Li,Conghu Liu,Guang Zhu,Zhifeng Liu 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.3

Selective laser melting (SLM) can form complex and precise metal parts simultaneously and is widely used in medical and aerospace fields. The support structure plays an important role in SLM process, including supporting the overhanging structure, dissipating heat, and minimizing geometric deformation caused by internal stress. However, a non-optimal support structure causes increased energy and material consumption during processing and must be removed afterward to allow for utilization of the parts. Existing support structure design methods only consider reducing the support of a single part, and research on the support and energy consumption of simultaneous multi-part printing is lacking. Therefore, to reduce the energy and material consumption of simultaneous multi-part printing by SLM and improve processing efficiency, an energy consumption analysis and optimization method is proposed in this study from the perspective of the support structure. Based on previous studies on energy consumption distribution of the additive manufacturing process, a multi-component SLM energy consumption and material consumption model was established. Furthermore, a shared-support optimization strategy for simultaneous multi-part processing is proposed. For optimization, the method selects the appropriate printing direction of one part, and then combines multiple parts to form a shared support structure to minimize energy consumption. Finally, under the constraint of minimizing the mass, an optimization strategy of the SLM multi-part shared support combination is established, and the purpose of reducing the energy consumption and material consumption of the SLM is achieved under the premise of ensuring the geometric accuracy of the parts. The method was applied to the manufacturing process of a group of parts with a beam structure. Compared with the printing method using independent support, the shared support structure method reduced energy consumption more than 5.5%, material consumption for the support structure more than 17.2%, and printing time to a certain extent. This method effectively improves SLM production efficiency and sustainability and provides strategic support for additive manufacturing designers and producers.

LIGHT-HVEM Signaling in Innate Lymphoid Cell Subsets Protects Against Enteric Bacterial Infection

Seo, Goo-Young,Shui, Jr-Wen,Takahashi, Daisuke,Song, Christina,Wang, Qingyang,Kim, Kenneth,Mikulski, Zbigniew,Chandra, Shilpi,Giles, Daniel A.,Zahner, Sonja,Kim, Pyeung-Hyeun,Cheroutre, Hilde,Colonna, Elsevier 2018 Cell host & microbe Vol.24 No.2

<P><B>Summary</B></P> <P>Innate lymphoid cells (ILCs) are important regulators of early infection at mucosal barriers. ILCs are divided into three groups based on expression profiles, and are activated by cytokines and neuropeptides. Yet, it remains unknown if ILCs integrate other signals in providing protection. We show that signaling through herpes virus entry mediator (HVEM), a member of the tumor necrosis factor (TNF) receptor superfamily, in ILC3 is important for host defense against oral infection with the bacterial pathogen <I>Yersinia enterocolitica.</I> HVEM stimulates protective interferon-γ (IFN-γ) secretion from ILCs, and mice with HVEM-deficient ILC3 exhibit reduced IFN-γ production, higher bacterial burdens and increased mortality. In addition, IFN-γ production is critical as adoptive transfer of wild-type but not IFN-γ-deficient ILC3 can restore protection to mice lacking ILCs. We identify the TNF superfamily member, LIGHT, as the ligand inducing HVEM signals in ILCs. Thus HVEM signaling mediated by LIGHT plays a critical role in regulating ILC3-derived IFN-γ production for protection following infection.</P> <P><B>Video Abstract</B></P> <P>Display Omitted</P> <P><B>Highlights</B></P> <P> <UL> <LI> ILC3 are required for early host defense during <I>Y. enterocolitica</I> infection </LI> <LI> IFN-γ from CCR6<SUP>−</SUP> ILC3 is essential for protection of mice from <I>Yersinia</I> </LI> <LI> HVEM expression by ILC3 is important for IFN-γ production following infection </LI> <LI> LIGHT is the ligand for HVEM signaling in regulating ILC3-derived IFN-γ production </LI> </UL> </P> <P><B>Graphical Abstract</B></P> <P>[DISPLAY OMISSION]</P>