High-speed impact behavior of a casting AM80 magnesium alloy under various deformation temperatures
作者：
Guo, Pengcheng;Li, Luoxing* ;Xiao, Gang;Cao, Shufen;Wang, Guan;...
期刊：
Journal of Alloys and Compounds ,2019年811:151875 ISSN：0925-8388
通讯作者：
Li, Luoxing
作者机构：
[Guo, Pengcheng; He, Hong; Xiao, Gang; Cao, Shufen; Li, Luoxing] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Guo, Pengcheng] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.;[Wang, Guan] Ningxia Univ, Coll Mech Engn, Yinchuan 750021, Peoples R China.
通讯机构：
[Li, Luoxing] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
Deformation;Dynamic recrystallization;Dynamics;Grain boundaries;Magnesium castings;Mechanical testing;Microstructure;Shear bands;Strain rate;Adiabatic temperature rise;Deformation temperatures;Dynamic recrystallization (DRX);High speed impact;Mechanical twinning;Mg alloy;Recrystallized microstructures;Split Hopkinson Pressure Bar test;Magnesium alloys
摘要：
Split-Hopkinson pressure bar tests were conducted on a solution-treated cast AM80 Mg alloy at 298, 423 and 523 K with strain rates (SRs) ranging from 1100 s−1 to 5000 s−1. The effects of the SR and temperature on the high-speed impact behavior and corresponding microstructure evolution were investigated. The results indicate that the flow stress behavior of the studied alloy strongly depends on the applied SR and deformation temperature. At all temperatures, the SR sensitivity (SRS) changes from positive to negative values as the applied SRs increase to their critical values. Several adiabatic shear bands (ASBs) appear at 298 K with a SR of 5000 s−1. At elevated temperatures of 423 and 523 K, mechanical twins and dislocations are gradually replaced by dynamically recrystallized grains with increasing SR. A fully recrystallized microstructure forms as the applied SR increases to 5000 s−1. The Dynamic recrystallization (DRX) is mainly induced by twinning that preferentially nucleates at the twin boundaries and intersections between the twin boundaries and grain boundaries. The adiabatic temperature rise and corresponding microstructure evolution, including the ASBs and DRX, are attributed to the negative SRS of the studied alloy because the applied SRs exceed their critical values. © 2019 Elsevier B.V.
语种：
英文
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机械制图在线开放课程助力混合式教学的探索与实践
作者：
李玲;李卉;于水琴
期刊：
高教学刊 ,2019年(11):13-16 ISSN：2096-000X
作者机构：
中南林业科技大学 机电工程学院,湖南 长沙,410004;[李卉; 于水琴; 李玲] 中南林业科技大学
关键词：
《机械制图》;在线开放课程;混合式教学
摘要：
在本科教育高度重视的当今,进行教育创新,搭建基于学生主动学习能力培养的线上线下混合式教学平台,尝试和实践一些崭新有效的教学手段和方式,势在必行。为此,我们将《机械制图》课程打造成教学内容齐备、教学资源丰富、功能设计合理、学习使用便捷的在线开放课程,实施课内与课外相结合、线上与线下相结合、教师课堂面授与学生自主学习相结合的混合式教学模式,构建以学生为中心的教与学新型关系,从而促进学生自主学习、主动学习、合作学习,培养学生解决复杂问题的综合能力和科学思维的能力。
语种：
中文
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《机电一体化系统设计》课程思政的教学探索与思考
作者：
文韬;龚中良;韩庆珏;辜良瑶;李玲
期刊：
农业工程与装备 ,2019年46(7):102-104 ISSN：2096-8736
作者机构：
中南林业科技大学机电工程学院,湖南 长沙,410004;[龚中良; 文韬; 辜良瑶; 韩庆珏; 李玲] 中南林业科技大学
关键词：
课程思政;机电一体化;专业课程
摘要：
目前我国高校机械类工科专业教育只注重向学生传授知识和专业技能,对思政教育的重视力度不够,未有效衔接和贯穿立德树人的教育理念问题。文章以机械类核心专业课程《机电一体化系统设计》为例,分析了当前专业课程教学存在的弊端,并针对课程的性质和特点,提出了课程思政改革的目标,探讨了课程思政教学体系的构建、教学过程的实施和教学效果的评价。
语种：
中文
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机械制图之“相贯线”课堂教学优化与实践
作者：
李玲;李卉
期刊：
教育教学论坛 ,2017年(33):134-135 ISSN：1674-9324
作者机构：
中南林业科技大学 机电工程学院,湖南 长沙,410004;[李卉; 李玲] 中南林业科技大学
关键词：
机械制图;相贯线;教学优化
摘要：
"相贯线"这部分内容是《机械制图》课程教学中的重点和难点.如何让形象思维与构形能力参差不齐的工科大学生短时间内有效地理解和掌握,一直是各个高校从事制图教学的教师重视和思考的问题.较之传统的授课方式,笔者对本教学内容做了精心设计和优化,丰富教学手段和资源,突出重点,收到了良好的效果.
语种：
中文
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基于Creo Param etric的机械制图助学型交互式课件的开发与应用
作者：
李玲;李卉;于水琴
期刊：
教育教学论坛 ,2017年(37):196-197 ISSN：1674-9324
作者机构：
中南林业科技大学机电工程学院,湖南 长沙,410004;[李卉; 于水琴; 李玲] 中南林业科技大学
关键词：
机械制图;交互式课件
摘要：
近些年随着三维造型技术的介入和迅猛发展,其造型设计的直观、动态、快捷及实时性等优点,能帮助学生快速建立"体"这一概念,有效拓展空间思维能力,较之传统的教学手段学生对于教学内容的理解显得更加透彻.本教学团队利用Creo Parametric软件强大的三维建模功能和方便的可视化实时动态观察、截切等功能,精心制作了一套难度适宜的三维立体教学模型库,并将其与现有的课程资源进行了创新与融合,开发制作出一套适合机械类专业学生的助学型交互式课件.
语种：
中文
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Modeling the effect of injection molding process parameters on warpage using neural network theory
作者：
Li, Qingchun;Li, Lijun;Si, Xiaojie;Wang, Rongji*
期刊：
JOURNAL OF MACROMOLECULAR SCIENCE PART B-PHYSICS ,2015年54(9):1066-1080 ISSN：0022-2348
通讯作者：
Wang, Rongji
作者机构：
[Li, Qingchun; Si, Xiaojie; Wang, Rongji; Li, Lijun] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Wang, Rongji] C;Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.
关键词：
Backpropagation;Injection molding;Polypropylenes;Predictive analytics;Back propagation artificial neural network (BPANN);Injection molding process;Mold temperatures;Moldflow softwares;Orthogonal design method;Process parameters;Reasonable accuracy;Warpages;Neural networks
摘要：
A back propagation artificial neural network (BPANN) prediction model for warpage of injection-molded polypropylene was developed based on an orthogonal design method. The BPANN model was trained by the input and output data obtained from the moldflow software platform simulations. It is proved that the BPANN model can predict the warpage with reasonable accuracy. Utilizing the BPANN model, the effects of the process parameters, packing pressure (Pp), melt temperature (Tme), mold temperature (Tmo), packing time (tp), cooling time (tc), and fill pressure (pf), on the warpage were investigated. The most important process parameter affecting the warpage was Pp, and the second most important was Tme. The rest of the process parameters, Tmo, tp, tc, and pf, were found to be relatively less influential. Warpage increased with elevating Tmo. In contrast, an increase in Pp and Tme caused the warpage to decrease. © 2015 Taylor and Francis Group, LLC.
语种：
英文
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Influence of pressure and surface roughness on the heat transfer efficiency during water spray quenching of 6082 aluminum alloy
作者：
Xu, Rong;Li, Luoxing* ;Zhang, Liqiang;Zhu, Biwu;Liu, Xiao;...
期刊：
Journal of Materials Processing Technology ,2014年214(12):2877-2883 ISSN：0924-0136
通讯作者：
Li, Luoxing
作者机构：
[Bu, Xiaobing; Xu, Rong; Zhang, Liqiang; Zhu, Biwu; Liu, Xiao; Li, Luoxing] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Bu, Xiaobing; Xu, Rong; Li, Luoxing] Hunan Univ, Coll Mech & Vehicle Engn, Changsha 410082, Hunan, Peoples R China.;[Zhang, Liqiang] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.;[Zhu, Biwu; Liu, Xiao] Hunan Univ Sci & Technol, Coll Electromech Engn, Xiangtan 411002, Hunan, Peoples R China.
通讯机构：
[Li, Luoxing] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
Atmospheric temperature;Crystallization;Heat conduction;Heat flux;Heat transfer coefficients;Inverse problems;Nucleation;Quenching;Surface properties;Surface roughness;Heat transfer efficiency;Interfacial heat transfer;Inverse heat conduction methods;Maximum heat transfer;Nucleation site density;Spray pressure;Spray quenching;Water spray quenching;Aluminum alloys
摘要：
The heat flux (q) and heat transfer coefficient (h) at the interface between hot aluminum surface and spray water were determined by using an inverse heat conduction method. Good agreements between numerically calculated temperatures with the inverse identified h and experimentally measurements demonstrate that the method is valid for solving the q and h of spray quenching process. The estimated heat flux consists of three main stages of transition boiling, nucleate boiling and single-phase cooling. The results show that both the heat flux and heat transfer coefficient increase with the increasing of spray pressure. When the surface temperature is lower than 170 °C, the q, h and the maximum heat transfer coefficient (hmax) decrease and then increase as surface roughness increases. However, when the surface temperature is higher than 170 °C, the influence of surface is insignificant. This phenomenon may be attributed to the variation of nucleation site density with surface roughness. © 2014 Elsevier B.V.
语种：
英文
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Dynamic simulation analysis of forest-fruit vibratory harvester arm
作者：
Jian Zhou;Lijun Li;Ye Xue
期刊：
Advance Journal of Food Science and Technology ,2014年6(1):130-134 ISSN：2042-4868
通讯作者：
Li, L.
作者机构：
[Zhou J.; Lijun Li; Xue Y.] Machinery and Electrical Engineering College, Centre South University of Forestry Science and Technology, Changsha, 410004, China
通讯机构：
Machinery and Electrical Engineering College, Centre South University of Forestry Science and Technology, China
关键词：
Computer aided design;Computer simulation;Dynamics;Forestry;Fruits;Harvesters;Software prototyping;Virtual prototyping;ADAMS;Dynamic simulation analysis;Dynamics simulation;Fruit harvesters;Mechanical characteristics;Picking machines;Pro/E software;System simulations;Computer software
摘要：
For obtaining excellent properties of vibration type picking machine of oil tea fruit, two and three dimensional virtual prototype of forest-fruit vibratory harvester was established by CAD and Pro/E software, then the dynamic prototype was converted and the dynamics simulation was worked out by the Adams system simulation software for the arm. The mechanical characteristics of arm were measured during positioning and vibrating the end of arm and they provide a theoretical references to optimize the physical prototype. © Maxwell Scientific Organization, 2014.
语种：
英文
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Determination of heat transfer coefficients at metal/chill interface in the casting solidification process
作者：
Zhang, Liqiang* ;Li, Luoxing
期刊：
Heat and Mass Transfer ,2013年49(8):1071-1080 ISSN：0947-7411
通讯作者：
Zhang, Liqiang
作者机构：
[Zhang, Liqiang] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.;[Zhang, Liqiang; Li, Luoxing] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Zhang, Liqiang] C;Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.
关键词：
Heat flux;Testing;Calculation parameters;Casting solidification;Casting solidification process;Heat conduction models;Interfacial heat transfer coefficients;Inverse algorithm;Least-squares techniques;Sequential function specification methods;Solidification
摘要：
The present work focuses on the determination of interfacial heat transfer coefficients (IHTCs) between the casting and metal chill during casting solidification. The proposed method is established based on the leastsquares technique and sequential function specification method and can be applied to calculate heat fluxes and IHTCs for other alloys. The accuracy and stability of the method has been investigated by using a typical profile of heat fluxes simulating the practical conditions of casting solidification. In the test process, the effects of various calculation parameters in the inverse algorithm are also analyzed. Moreover, numerically calculated and experimental results are compared by applying the determined IHTCs into the forward heat conduction model with the same boundary conditions. The results show that the numerically calculated temperatures are in good agreement with those measured experimentally. This confirms that the proposed method is a feasible and effective tool for determination of the casting-mold IHTCs. © Springer-Verlag Berlin Heidelberg 2013.
语种：
英文
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机械制图课程教学内容的优化与实践
作者：
李玲;刘慧玲
期刊：
农业工程与装备 ,2011年38(07):194-195 ISSN：2096-8736
作者机构：
中南林业科技大学机电工程学院,湖南长沙,410004;[刘慧玲; 李玲] 中南林业科技大学
关键词：
机械制图;教学内容;优化
摘要：
机械制图是工科院校机械类专业学生必修的一门重要的专业基础课,其主要任务是培养和训练学生具备一定的读图、绘图和空间构思能力。如何根据制图课程要求高、学时紧、内容多、实践时间短的特点并结合学生的实际情况来优化教学内容、改进教学方法、提高教学质量应该是教师不断探索的课题。实践表明,利用这些方法可获得较好的教学效果。
语种：
中文
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Plastic mold design of top-cover of out-shell of mouse based on CAE
作者：
Zhou, Jian* ;Li, Lijun;Hu, Yihua;Yang, Jianguo;Cheng, Ke
期刊：
Procedia Engineering ,2011年15:4441-4445 ISSN：1877-7058
通讯作者：
Zhou, Jian
作者机构：
[Zhou, Jian; Li, Lijun] Ctr South Univ Forestry & Technol, Machinery & Elect Engn Coll, Changsha 410004, Hunan, Peoples R China.;[Cheng, Ke; Hu, Yihua] Guangxi Univ Technol, Lushan Coll, Liuzhou 545006, Peoples R China.;[Yang, Jianguo] Zhuzhou Gear CO LTD, Zhuzhou 412000, Peoples R China.
通讯机构：
[Zhou, Jian] C;Ctr South Univ Forestry & Technol, Machinery & Elect Engn Coll, Changsha 410004, Hunan, Peoples R China.
会议名称：
International Conference on Advanced in Control Engineering and Information Science (CEIS)
会议时间：
AUG 18-19, 2011
会议地点：
Dali, PEOPLES R CHINA
会议主办单位：
[Zhou, Jian;Li, Lijun] Ctr South Univ Forestry & Technol, Machinery & Elect Engn Coll, Changsha 410004, Hunan, Peoples R China.^[Hu, Yihua;Cheng, Ke] Guangxi Univ Technol, Lushan Coll, Liuzhou 545006, Peoples R China.^[Yang, Jianguo] Zhuzhou Gear CO LTD, Zhuzhou 412000, Peoples R China.
会议论文集名称：
Procedia Engineering
关键词：
Plastic mold;Pro/E;Design
摘要：
The article analysis the product construction and manufacturing technology,aso points out the parting surface design, the cavity mold design and the punch mold design, calculating deformation parts working size, drawing of assembly and parts' graphes, manufacturing process of plastic mold. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [CEIS 2011]
语种：
英文
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高等学校机械基础课程体系教学改革研究
作者：
刘慧玲;李玲
期刊：
中国现代教育装备 ,2011年(21):75-77 ISSN：1672-1438
作者机构：
中南林业科技大学机电工程学院,湖南长沙,410004;[刘慧玲; 李玲] 中南林业科技大学
关键词：
机械基础课程体系;教学改革;创新
摘要：
构建机械基础课程体系;分析以创新为核心,以能力培养为主线,以贴近实际为切入点的教学改革模式;对理论课程和实验实践课程的教学内容、教学方法、教学手段以及考核模式进行了深入的研究。
语种：
中文
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Analysis of Cracking Properties of Camellia Oleifera Fruit Heated by Micro-wave
作者：
Li, Lijun* ;Zhou, Jian;Gao, Zicheng;Ming, Shuhui;Yang, Zhimin
期刊：
Procedia Engineering ,2011年15:4436-4440 ISSN：1877-7058
通讯作者：
Li, Lijun
作者机构：
[Zhou, Jian; Ming, Shuhui; Yang, Zhimin; Li, Lijun; Gao, Zicheng] Ctr S Univ Forestry & Technol, Machinery & Elect Engn Coll, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Li, Lijun] C;Ctr S Univ Forestry & Technol, Machinery & Elect Engn Coll, Changsha 410004, Hunan, Peoples R China.
会议名称：
International Conference on Advanced in Control Engineering and Information Science (CEIS)
会议时间：
AUG 18-19, 2011
会议地点：
Dali, PEOPLES R CHINA
会议主办单位：
[Li, Lijun;Zhou, Jian;Gao, Zicheng;Ming, Shuhui;Yang, Zhimin] Ctr S Univ Forestry & Technol, Machinery & Elect Engn Coll, Changsha 410004, Hunan, Peoples R China.
会议论文集名称：
Procedia Engineering
关键词：
Camellia oleifera;micro-wave;shell-cracking;crack
摘要：
As one of the chinese special product, it is very important for further machining of camellia oleifera fruit. The paper points out the fruit volume and density distribution, the specific heat capacity is about 2.1 similar to 2.5J/g degrees C. Under the microwave effect, the relation of critical fracture strength factor to rigidity has been calculated K-1c(2)= (1.1 similar to 9.8) *10(3)E. Practice and theory show that natural shape results the cracks locating the most raised parts of camellia oleifera fruit; Because the fibrous structure is the most weakness, the first cracking point is the fruit natural bottom. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [CEIS 2011]
语种：
英文
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