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Generation Mechanism of Interfacial Layer and Its Effect on Fe-Cr-Ni/Al-Si-Cu-Ni-Mg Composite Performance

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Journal of Wuhan University of Technology(Materials Science) 2017年第5期32卷 1193-1198页

作者：周灵展 YANG Liming ZHU Xiurong PENG yinjiang Faculty of Mechanical Engineering and Mechanics Ningbo University Ningbo 315211 China Ningbo Branchof China Ordnance Academy Ningbo 315103 China

Fe-Cr-Ni/Al-Si-Cu-Ni-Mg composite was taken as the experimental material. The chemical composition of interfacial layer was tested. The generation mechanism and influence of interfacial layer on the composite were analyzed. The results indicated that the generation of interfacial layer is sensitive to temperature. Interfacial layer will generate rapidly when temperature reaches 500 ℃ or above. The interfacial layer is mainly composed of Al, Si, Cu, Fe, and Cr, element Ni distributes at the outward of the interfacial layer for the precipitate of Ni later than Si and Cu, and there is almost no diffusion of Ni during the solution treatment. During heat treatment process, unequal quantity changing of metal atom results in disperse or concentrated vacancies or holes near the matrix. The existence of interfacial layer will induce a decrease of compression strength and plasticity at room temperature and an increase of strength at higher temperature comparing with composite without interfacial layer.

关键词： Fe-Cr-Ni composite interfacial layer influence

Comparative Study on Constitutive Models to Predict Flow Stress of Fe-Cr-Ni Preform Reinforced Al-Si-Cu-Ni-Mg Composite

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Journal of Wuhan University of Technology(Materials Science) 2017年第3期32卷 666-676页

作者：周灵展 YANG Liming PENG yinjiang FEI Liangjun ZHU Xiurong Faculty of Mechanical Engineering and Mechanics Ningbo University Ningbo 315211 China Ningbo Branch of China Ordnance Academy Ningbo 315103 China

The isothermal compression tests were carried out on Gleeble-3500 thermal-mechanical simulation machine in a temperature range of 298-473 K and strain rate range of 0.001-10 s^-1. The experimental results show that the flow stress data are negatively correlated with temperature for temperature softening, and the strain rates sensitivity of this composite increases with elevating temperature. Based on the experimental data, Johnson-Cook, modified Johnson-Cook and Arrhenius constitutive models were established. The accuracy of these three constitutive models was analyzed and compared. The results show that the values predicted by Johnson-Cook model could not agree well with the experimental values. The prediction accuracy of Arrhenius model is higher than that of Johnson-Cook model but lower than that of the Modified Johnson-Cook model.

关键词： Fe-Cr-Ni porous preform composite isothermal compression constitutive model

Experimental study on variable load regulation of circulating fluidized bed with high temperature preheated activated fuel

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PARTICUOLOGY 2024年第12期95卷 178-188页

作者： Song, Weijian Tang, Zihua Song, Guoliang Zhu, Jianguo Liu, Jingzhang Wang, Haiyang Zhang, yinjiang Chinese Acad Sci Inst Engn Thermophys State Key Lab Coal Convers Beijing 100190 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Datong Inst Coal Clean & Efficient Utilizat Datong 037000 Peoples R China

The circulating fluidized bed (CFB) boiler is an essential option, serving as a flexible power source. However, it is notable that CFB boilers exhibit noticeable limitations in rapid load changes. This study delved into the impact of fuel characteristics on CFB load change rate, combustion efficiency, and original NOx emissions using a 2 MW CFB experimental platform. The findings revealed that blending pulverized coal or modified fuel positively influenced the improvement of CFB load change rate, with blending modified fuel showing a more significant effect. Blending the modified fuel and pulverized coal increased the load change rate within the 50%-100% range by 164.4% and 57.3%, respectively. Additionally, blending pulverized coal and modified fuel significantly reduced NOx emissions, although there remained room for improvement in combustion efficiency. Compared to conventional combustion, blending pulverized coal and blending modified fuel decreased NOx emissions by 35.9% and 41.4% at 100% load, respectively. (c) 2024 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Circulating fluidized bed Pulverized coal Modified char Coal gas Load change rate NO x emission

Novel obstacle-avoiding path planning for crop protection UAV using optimized Dubins curve

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International Journal of Agricultural and Biological Engineering 2020年第4期13卷 172-177页

作者： Xihai Zhang Chengguo Fan Zhanyuan Cao Junlong Fang yinjiang Jia College of Electronics and Information Northeast Agricultural UniversityHarbin 150000China

In recent years,the crop protection unmanned aerial vehicle(UAV)has been raised great attention around the world due to the advantages of more efficient operation and lower requirement of special landing ***,there are few researches on obstacle-avoiding path planning for crop protection *** this study,an improved Dubins curve algorithm was proposed for path planning with multiple obstacle ***,according to the flight parameters of UAV and the types of obstacles in the field,the obstacle circle model and the small obstacle model were ***,after selecting the appropriate Dubins curve to generate the obstacle-avoiding path for multiple obstacles,the genetic algorithm(GA)was used to search the optimal obstacle-avoiding ***,for turning in the path planning,a strategy considering the size of the spray width and the UAV’s minimum turning radius was presented,which could decrease the speed change *** results showed that the proposed algorithm can decrease the area of overlap and skip to 205.1%,while the path length increased by only 1.6%in comparison with the traditional Dubins obstacle-avoiding algorithm under the same *** the increase of obstacle radius,the area of overlap and skip reduced effectively with no significant increase in path ***,the algorithm can efficiently improve the validity of path planning with multiple obstacle constraints and ensure the safety of flight.

关键词： Dubins curve path planning genetic algorithm overlap and skip spray crop protection UAV

Impact characteristics analysis of a parachute-free airdrop box with a composite structure

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Zhendong yu Chongji/Journal of Vibration and Shock 2024年第24期43卷 323-331页

作者： Shi, Yongsheng Wang, yinjiang College of Aeronautical Engineering Civil Aviation University of China Tianjin 300300 China

To promote the development of parachute-free airdrop technology, the impact characteristics of a parachute-free airdrop box with a composite structure were studied, and the impact response and failure modes were analyzed. The protection mechanism of the parachute-free airdrop box was analyzed theoretically, which was simulated by finite element method. The Simulation results show that the goods with edge drop and angle drop have large displacement, serious box deformation and long impact duration;the impact energy absorption rate of the parachute-free airdrop box is more than 80%, and the efficient energy absorption provides a strong guarantee for goods safety;compared with edge drop and angle drop, the peak acceleration and average impact force of goods are larger for face drop;when the edge drop and the angle drop, the stress and strain level of the parachute-free airdrop box is higher than the face drop. The study shows that the safety of goods is related to the impact area and foam impact thickness, smaller impact area and larger foam thickness can reduce the risk of goods damage;the failure of the parachute-free airdrop box is related to their impact area. Larger impact area can effectively reduce the degree of impact failure and improve the safety of goods. © 2024 Chinese Vibration Engineering Society. All rights reserved.

关键词： Parachutes

Rotifer community structure and its response to environmental factors in the Backshore Wetland of Expo Garden,Shanghai

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Aquaculture and Fisheries 2018年第2期3卷 90-97页

作者： Liping Yin Yu Ji yinjiang Zhang Linxuan Chong Lijing Chen National Demonstration Center for Experimental Fisheries Science Education Shanghai Ocean UniversityShanghai 201306China Key Laboratory of Freshwater Aquatic Genetic Resources Ministry of AgricultureShanghai Ocean UniversityShanghai 201306China Shanghai Collaborative Innovation for Aquatic Animal Genetics and Breeding Shanghai Ocean UniversityShanghai 201306China Shanghai Universities Engineering Research Center of Water Ecological Environment Shanghai Ocean UniversityShanghai 201306China

We investigated rotifer community structure in the Backshore Wetland of the Expo Garden in Shanghai from September 2009 to August *** identified 116 rotifer species,determined the dominant species and their relationships with environmental factors,and community diversity *** trigla was the most common species over the four seasons and proportionally most dominant in spring and autumn,whereas Cephalodella exigua and Keratella cochlearis were the most dominant species in winter and summer,*** was seasonal variability in species numbers,with the highest numbers in summer,followed by autumn and *** mean annual density was 815±1346 ind./L and the biomass was 0.3649±0.4940 mg/*** were significant differences between months:the highest density(2723±2926 ind./L)and biomass(0.7938±0.8197 mg/L)occurred in June,while the lowest density(238±271 ind./L)and biomass(0.0476±0.0429 mg/L)occurred in *** correspondence analysis(CCA)indicated that temperature,pH,nitrite nitrogen(NO2-N),and total phosphorus(TP)were the most important abiotic factors affecting rotifer *** research showed that the adaptability of the rotifers to temperature was the important factor.

关键词： Backshore Wetland Rotifer Community structure Environmental factor

Pb Distribution and Sources in Jiaozhou Bay, East China

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Journal of Water Resource and Protection 2011年第1期3卷 41-49页

作者： Dongfang Yang Junhui Guo yinjiang Zhang Ziru Ding Zhiguo Bu 不详

We studied the distribution, seasonal change, translocation, and source of heavy metal Pb based on the surface and bottom water sampling in Jiaozhou Bay in 1980 in order to know the condition of Pb before the industrial and agricultural development and to probe the distribution and translocation process of Pb. The results show that the range of Pb content in the surface in the whole bay was 0.07-2.71 μg/L, being below Grade Ⅱ of the China’s national water quality benchmark (5.00 μg/L). No Pb pollution was detected in the inner bay, while in the outer bay and the mouth, light Pb pollution. The Pb pollution in the bay waters was area sources. Horizontal and vertical distribution, and seasonal change indicated the translocation of Pb in the waters. Pb entered the water body at marine surface and sank at the marine bottom. Understanding the variable process of Pb in the bay provided the scientific clues for controlling Pb pollution from the human activities.

关键词： Heavy Metal Pb Distribution Seasonal Change Pollution Source Jiaozhou Bay

Ti-5Al-2.5Sn粉末颗粒界面在热等静压过程中的变化

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稀有金属材料与工程 2000年第5期29卷 336-339页

作者：吴引江兰涛周廉金志浩西北有色金属研究院西安710016 西安交通大学材料与工程学院西安710049

采用等离子旋转电极 (PREP) Ti- 5 Al- 2 .5 Sn粉末 ,经过热等静压 (HIP)工艺研究原始粉末界面在热等静压致密化过程中的变化。研究结果表明 :由于原始粉末颗粒界面存在成分偏析、氧化和杂质元素富集等 ,在致密化过程中粉末颗粒界面经... 详细信息

采用等离子旋转电极 (PREP) Ti- 5 Al- 2 .5 Sn粉末 ,经过热等静压 (HIP)工艺研究原始粉末界面在热等静压致密化过程中的变化。研究结果表明 :由于原始粉末颗粒界面存在成分偏析、氧化和杂质元素富集等 ,在致密化过程中粉末颗粒界面经历了变形、破裂、偏聚和均匀化等一系列复杂的变化过程。同时这些界面物质的存在使得材料的粉末颗粒界面结合力变差。为了避免它对材料最终性能的影响。

关键词：粉末颗粒界面热等静压 Ti-5Al-2.5Sn

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注射成形用金属粉末的制备技术研究进展

稀有金属材料与工程 2010年第A01期39卷 496-500页

作者：郭晓梅吴引江东北大学辽宁沈阳110819 西北有色金属研究院宝德公司陕西西安710016

概述国内金属粉末的的制备技术和研究进展,重点介绍注射成形用金属粉末的技术要求和主要制备技术。分析未来国内工业生产注射成形用金属粉末的发展方向,并提出等离子体技术将成为生产MIM用金属粉末首要考虑的方法。

关键词： MIM 金属粉末制备技术