Effect of coatings on thermal conductivity and tribological properties of aluminum foam/polyoxymethylene interpenetrating composites
作者：
Dong, Peiran* ;Long, Chunguang;Peng, Ying;Peng, Xin;Guo, Fangyu
期刊：
Journal of Materials Science ,2019年54(20):13135-13146 ISSN：0022-2461
通讯作者：
Dong, Peiran
作者机构：
[Dong, Peiran; Peng, Ying; Long, Chunguang; Peng, Xin] Changsha Univ Sci & Technol, Inst Automobile & Mech Engn, Changsha 410114, Hunan, Peoples R China.;[Long, Chunguang] Coll Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.;[Guo, Fangyu] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Dong, Peiran] C;Changsha Univ Sci & Technol, Inst Automobile & Mech Engn, Changsha 410114, Hunan, Peoples R China.
摘要：
The purpose of this work is to solve the problem of interface bonding in aluminum foam (AF)/polyoxymethylene (POM) interpenetrating phase composites (AF/POM). Silane coupling agent (KH-550), graphene oxide (GO), sulfonated graphene (S-GNS) and graphene (GS) coatings were prepared on the surface of AF, respectively, as an interfacial transition layer. The molten modified POM(POMC) was injected into the hole of coated AF by injection molding to prepare different kinds of coated AF/POMC. Thermal conductivity, friction coefficient and wear loss of coated AF/POMC were analyzed, and the wear mechanisms were discussed in detail based on evidences from SEM. The effect of coatings on thermal conductivity of coated AF/POMC was also verified by ANSYS. The investigation has shown that four kinds of coating are successfully covered on the surface of AF, respectively, and the morphology of S-GNS coating is the smoothest. The thermal conductivity of coated AF/POMC is higher than that of AF/POMC. The thermal conductivity of S-GNS-AF/POMC reaches the highest value of 2.25 W m−1 K−1, because S-GNS coating plays a role in reducing the thermal resistance of the interface between AF and POMC phases. The friction coefficient and wear loss of coated AF/POMC are also lower than that of AF/POMC. Three types of graphene coating(S-GNS,GO,GS) as an interface transition layer between AF and POMC phases can homogenize friction, accelerate heat transfer and reduce the friction coefficient and wear loss of composites. Through ANSYS thermal steady-state simulation, S-GNS-AF/POMC has the maximum number of heat flow paths and the highest heat flux compared with other materials. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.
语种：
英文
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聚甲醛/海泡石纤维复合材料的制备与性能研究
作者：
付扬威;龙春光;董佩冉
期刊：
中国塑料 ,2019年33(2):24-28 ISSN：1001-9278
作者机构：
长沙理工大学汽车与机械工程学院,长沙,410004;[付扬威; 董佩冉; 龙春光] 长沙理工大学
关键词：
聚甲醛;海泡石纤维;复合材料;力学性能;摩擦学性能
摘要：
为制备性能优良的聚甲醛（POM）基复合材料,以海泡石纤维（Sep）填充POM制备POM/Sep复合材料。研究硅烷偶联剂KH550表面改性填料对复合材料力学和摩擦学性能的影响。复合材料的力学性能以及摩擦学性能随着Sep含量的增加而改善,当有机改性海泡石纤维（O-Sep）含量为5.0%（质量分数,下同）时,POM/O-Sep复合材料的拉伸强度、弯曲强度、弯曲模量和冲击性能分别达到最优值68.43 MPa、89.81 MPa、3600.61 MPa和285.5 kJ/m2,与纯POM相比提高了28.6%、51.9%、79.1%和8.8%;且POM/5.0%O-Sep复合材料的摩擦因数和磨损量分别达到0.072和3.6 mg,与纯POM相比降低了65.9%和35.7%。
语种：
中文
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高性能6061铝合金的热变形行为研究
作者：
刘思佳;龙春光;董佩冉;彭鹰;彭鑫
期刊：
世界有色金属 ,2018年(9):242-243 ISSN：1002-5065
作者机构：
长沙理工大学 汽车与机械工程学院 , 湖南 长沙 410114;长沙理工大学 轻量化新材料研究所,湖南 长沙 410114;长沙理工大学 汽车与机械工程学院 ,湖南 长沙,410114;[彭鹰; 董佩冉; 龙春光; 刘思佳; 彭鑫] 长沙理工大学
关键词：
6061铝合金;热变形;塑性变形
摘要：
本文采用Gleeble-3500热模拟试验进行高温热变形压缩试验,研究6061 锻造铝合金在0.001-10s-1之间不同变形速率和375℃～500℃不同变形温度下的热变形流变行为。研究结果表明,6061铝合金的流变应力随应变速率的升高而增大,随着热变形温度的升高而减小。
语种：
中文
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漆籽壳纤维含量对聚甲醛/玄武岩纤维复合材料的力学及摩擦学性能的影响
作者：
刘俊鹏;龙春光;谌磊;付扬威;许可可;...
期刊：
中国塑料 ,2017年31(4):40-44 ISSN：1001-9278
作者机构：
[刘俊鹏; 龙春光; 谌磊; 付扬威; 许可可; 董佩冉] 长沙理工大学汽车与机械工程学院, 湖南, 长沙, 410004
关键词：
漆籽壳纤维;玄武岩纤维;聚甲醛;摩擦学性能
摘要：
采用熔融共混、注射成型等工艺制备了聚甲醛(POM)/玄武岩纤维(BF)/漆籽壳纤维(LSSF)复合材料,通过力学试验、摩擦磨损试验和扫描电子显微镜分别研究了复合材料的力学性能、摩擦学性能和微观形貌。结果表明,LSSF和BF较均匀地分散于POM基体中,且界面相容性较好;POM/BF/LSSF复合材料的冲击性能、流动性能和摩擦性能相对于POM/BF复合材料都有一定的提高;与POM/20%BF相比,当LSSF的添加量为10%(质量分数,下同)时,复合材料的流动性能提高了68%;当LSSF添加量为15%时,复合材料的冲击性能提高了225%;当LSSF添加量为5%时,复合材料的摩擦因数降低了23%,磨损量降低了70%;复合材料的主要磨损机制由低漆籽壳含量时的磨粒磨损转变为高漆籽壳含量时的磨粒磨损和黏着磨损复合作用。
语种：
中文
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学生互评在大学课程考核中的作用与实践
作者：
余小峰;张健;龙春光;谢炜;曹太山
期刊：
时代教育 ,2017年(17):23 ISSN：1672-8181
作者机构：
长沙理工大学汽车与机械工程学院,湖南长沙,410114;[龙春光; 曹太山; 谢炜; 张健; 余小峰] 长沙理工大学
关键词：
课程考核;学生互评;自我学习
摘要：
本文针对当前课程考核过程中以老师为主的弊端,通过引入“学生互评”来增强考核过程的全面性并促进学生的学习积极性.通过不同的教学实践过程探讨了“学生互评”在课程考核过程中需要注意的事项.
语种：
中文
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漆籽壳纤维（LSSF）增强HDPE/UHMWPE复合材料摩擦学性能
作者：
龙春光;谌磊;刘俊鹏;付扬威;许可可;...
期刊：
长沙理工大学学报(自然科学版) ,2017年14(1):92-97 ISSN：1672-9331
作者机构：
长沙理工大学 汽车与机械工程学院,湖南 长沙,410004;[许可可; 付扬威; 龙春光; 谌磊; 刘俊鹏; 余小峰] 长沙理工大学
关键词：
漆籽壳纤维;流动性;摩擦学性能;磨粒磨损;黏着磨损;摩擦系数;磨损量
摘要：
大多数水泵失效都是由于水泵导轴承的磨损毁坏而引起的,而水泵在含泥沙水体中的应用加重了水泵导轴承的磨损程度,因此,研制一种新的自润滑耐磨复合材料来代替传统金属材料用于水泵导轴承制造是一种趋势。以高密度聚乙烯（HDPE）、超高分子量聚乙烯（UHMWPE）为基体,漆籽壳纤维（LSSF）为填料,通过熔融共混、注射成型制备了LSSF/HDPE/UHMWPE复合材料,研究了复合材料的流动性和摩擦学性能。研究结果发现,LSSF能提高复合材料的熔体流动速率,并随着LSSF含量的增加而增加,当添加的纤维含量为20%时,熔体流动速率提高了38.4倍;LSSF增强的HDPE/UHMWPE复合材料的摩擦系数和磨损量都低于HDPE/UHMWPE复合材料,当添加的纤维含量为15%时,摩擦系数和磨损量分别降低了60%和72.9%。分析复合材料磨痕的SEM照片得出,磨粒磨损和黏着磨损是主要的磨损机理。
语种：
中文
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PTW增强POM/TPU复合材料的制备及性能研究
作者：
许可可;龙春光;付扬威;董佩冉;刘思佳
期刊：
中国塑料 ,2017年31(6):41-45 ISSN：1001-9278
作者机构：
[许可可; 龙春光; 付扬威; 董佩冉; 刘思佳] 长沙理工大学汽车与机械工程学院, 湖南, 长沙, 410004
关键词：
聚甲醛;钛酸钾晶须;热塑性聚氨酯弹性体;增强
摘要：
以钛酸钾晶须(PTW)为增强体,采用熔融共混和注射成型法,制备了聚甲醛(POM)/热塑性聚氨酯弹性体(TPU)/PTW复合材料。研究了PTW含量对POM/TPU复合材料力学性能的影响,并借助扫描电子显微镜(SEM)分析了冲击断面形貌。结果表明,TPU的加入有效改善了纯POM的韧性,当TPU含量为10%(质量分数,下同)时,缺口冲击强度是纯POM的2.5倍,但拉伸强度和弯曲强度有所下降;PTW的加入对POM/TPU有较好的增强效果,当PTW含量为15%时,复合材料的拉伸强度、拉伸模量、断裂伸长率、弯曲强度、弯曲模量、缺口冲击强度分别为35.91MPa、24.17%、144.94MPa、12.26GPa、112.1kJ/m~2,拉伸模量、弯曲模量、缺口冲击强度与POM/TPU相比分别提高了14.7%、54.2%和9.2%,综合力学性能达到最佳。
语种：
中文
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机械大类专业《工程材料及热成型工艺》课程教改研究
作者：
戴晓元;华熳煜;罗奕兵;龙春光;寇莉莉
期刊：
科技创新导报 ,2017年14(34):229-230 ISSN：1674-098X
作者机构：
长沙理工大学汽车与机械学院 湖南长沙 410004;[华熳煜; 戴晓元; 龙春光; 罗奕兵; 寇莉莉] 长沙理工大学
关键词：
工程材料;热成型工艺;教学改革
摘要：
分析了机械大类专业对《工程材料及热成型工艺》课程的要求和课程教学效果不理想的原因,提出了课程教学内容、方法、考核形式的有关改革措施,以着重提高学生的学习兴趣和学生的工程技术应用能力为目的,使课程的教学更适合社会经济发展对高质量机械大类专业人才的要求。
语种：
中文
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高等学校专业导论课程教学实践与思考
作者：
谢炜;龙春光;华熳煜
期刊：
教育教学论坛 ,2016年(13):135-137 ISSN：1674-9324
作者机构：
长沙理工大学 汽车与机械工程学院,湖南 长沙,410114;[华熳煜; 龙春光; 谢炜] 长沙理工大学
关键词：
专业导论课;教学方法;教学实践
摘要：
鉴于高校专业导论课程对90后大学新生后续学习的重要性,本文从运用现代教学手段、科研与教学相结合、培养自主学习及课程考核等方面进行了探索和尝试,结合课堂教学取得的效果对专业导论课的教学改革进行了思考,以期对专业导论课的教学研究提供借鉴。
语种：
中文
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材料成型及控制工程专业本科生工程实践能力培养初探
作者：
张健;余小峰;龙春光;华熳煜;戴晓元;...
期刊：
建材与装饰(中旬刊) ,2016年(16):198-199 ISSN：1673-0038
作者机构：
长沙理工大学汽车与机械工程学院;[华熳煜; 戴晓元; 龙春光; 罗奕兵; 张健; 余小峰] 长沙理工大学
关键词：
工程实践能力培养;材料成型及控制工程;初探
摘要：
加强工程意识和工程实践能力的培养是当今工科类院校本科生教育的重要内容.笔者基于本校材料成型及控制工程本科专业多年的办学经验,对该专业本科生工程实践能力培养方面存在的问题及改革措施进行了初探.
语种：
中文
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CrAlN硬质刀具涂层的相结构稳定性及其热分解机制
作者：
张健;汤旺;毛聪;唐昆;余小峰;...
期刊：
中国有色金属学报 ,2016年26(1):88-95 ISSN：1004-0609
通讯作者：
Zhang, Jian(zj4343@126.com)
作者机构：
[毛聪; 张健; 龙春光; 余小峰; 唐昆; 汤旺] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China;[彭平] College of Materials Science and Engineering, Hunan University, Changsha, China;[毛聪; 张健; 龙春光; 余小峰; 唐昆; 汤旺] Key Laboratory of Security Design and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China
通讯机构：
Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China
关键词：
硬质刀具涂层;相结构稳定性;热分解机制;第一性原理计算
摘要：
采用基于密度泛函理论的第一性原理计算方法,从理论上系统研究不同Al固溶浓度x(x=0~1)下面心立方(FCC)结构Cr_(1-x)Al_xN硬质刀具涂层的微观几何构型、相结构稳定性及其热分解机制,并从电子结构角度对其稳定性起源进行分析。结果表明:随着Al固溶浓度增大,FCC-Cr_(1-x)Al_xN晶胞逐渐收缩,而其晶格畸变程度却先增大后减小,且当Al浓度x为0.5~0.75时,FCC-Cr_(1-x)Al_xN晶格畸变较为严重,为析出密排六方(HCP)结构的AlN化合物提供源动力;随着Al固溶浓度增大,FCC-Cr_(1-x)Al_xN相结构稳定性逐渐降低,且其极易按FCC-Cr_(1-x)Al_xN→(FCC-CrN)+(HCP-AlN)→(HCP-Cr_2N)+N_2+(HCP-AlN)的路径进行分解,计算结果与实验保持一致;Al固溶致使FCC-Cr_(1-x)Al_xN相结构稳定性降低的内在原因在于Cr_(1-x)Al_xN晶胞中Cr-N共价键作用随Al固溶度的增大而逐渐减弱。
语种：
中文
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Mechanical and Tribological Properties of Short Basalt Fiber-reinforced Polyoxymethylene Composites
作者：
Liu, Chenghe;Long, Chunguang* ;Chen, Lei;Liu, Junpeng;Cao, Taishan;...
期刊：
POLYMER-KOREA ,2016年40(6):836-845 ISSN：0379-153X
通讯作者：
Long, Chunguang
作者机构：
[Zhang, Jian; Chen, Lei; Liu, Chenghe; Long, Chunguang; Cao, Taishan; Liu, Junpeng] Changsha Univ Sci & Technol, Inst Automobile & Mech Engn, Changsha 410114, Hunan, Peoples R China.;[Zhang, Jian; Long, Chunguang; Cao, Taishan] Coll Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Long, Chunguang] C;Changsha Univ Sci & Technol, Inst Automobile & Mech Engn, Changsha 410114, Hunan, Peoples R China.;Coll Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.
关键词：
basalt fibers;polyoxymethylene;mechanical properties;tribological properties
摘要：
In this paper, short basalt fiber-reinforced polyoxymethylene (POM) composites were prepared by melt blending and injection molding. The mechanical and tribological properties of the composites were studied by an orthogonal experiment. It was found that the optimal combination of fiber length 4 mm, fiber content 20 wt% and treated with KH550 would result in a comprehensive property which is 27.45% higher tensile strength, 9.65% higher impact strength and 18.11% higher flexural strength with compared to that of pure POM. But its tribological properties would be worse with the addition of the basalt fibers. After incorporating 10 wt% of polytetrafluoroethylene (PTFE) into the composites, the tribological properties of the composites was improved, closed to that of pure POM, with an insignificant decrease to their mechanical properties. Moreover, the morphology of fracture surfaces and worn surfaces evaluated by scanning electron microscopy showed good agreement with the results of the literature.
语种：
英文
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MgH_2-K_2Ti_6O_(13)-Ni球磨复合体系的微观结构与解氢性能
作者：
张健;汤旺;邵磊;余小峰;龙春光;...
期刊：
材料工程 ,2016年44(11):101-106 ISSN：1001-4381
通讯作者：
Zhang, Jian(zj4343@163.com)
作者机构：
[张健; 汤旺; 邵磊; 余小峰; 龙春光] College of Automobile and Mechanical Engineering, Changsha University of Science and Technology, Changsha;410114, China;Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha;[陈荐] Key Laboratory of Efficient and Clean Energy Utilization, Education Department of Hunan Province, Changsha;[张健; 余小峰; 龙春光] 410114, China<&wdkj&>Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha
通讯机构：
[Zhang, J.] C;College of Automobile and Mechanical Engineering, Changsha University of Science and Technology, Changsha, China
关键词：
掺杂;解氢性能
摘要：
采用机械球磨法制备了K_2Ti_6O_(13)晶须单独掺杂、以及K_2Ti_6O_(13)晶须与Ni粉复合掺杂的MgH_2储氢复合体系,并通过XRD,SEM,DSC等检测手段对其微观结构与解氢性能进行表征。结果表明:当K_2Ti_6O_(13)晶须单独掺杂于MgH_2时,K_2Ti_6O_(13)晶须起到助磨细化MgH_2晶粒的作用,同时还抑制了MgH_2颗粒的团聚,有效降低了MgH_2基体的解氢温度,且当K_2Ti_6O_(13)与MgH_2质量配比为3∶7时,MgH_2解氢性能的改善效果尤为明显,其解氢温度较纯MgH_2球磨体系降低了近75℃;此外,当K_2Ti_6O_(13)晶须和Ni粉末复合掺杂于MgH_2时,得益于K_2Ti_6O_(13)晶须的助磨细化MgH_2晶粒以及Ni固溶于MgH_2晶格致使其结构稳定性降低的双重作用,从而使得MgH_2基体的解氢温度较K_2Ti_6O_(13)晶须单独掺杂时进一步降低,相对于纯MgH_2球磨体系降低了近87℃。
语种：
中文
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玄武岩短纤维增强聚甲醛复合材料的力学性能和摩擦学性能
作者：
龙春光;刘成河;谌磊;刘俊鹏;曹太山
期刊：
长沙理工大学学报(自然科学版) ,2016年13(3):87-92 ISSN：1672-9331
作者机构：
长沙理工大学汽车与机械工程学院,湖南长沙,410004;[刘成河; 龙春光; 谌磊; 曹太山; 刘俊鹏] 长沙理工大学
关键词：
聚甲醛;玄武岩纤维;复合材料;力学性能;摩擦性能
摘要：
以聚甲醛（POM）为基体、玄武岩短纤维（BF）为增强材料,通过熔融共混、注塑成型制备了BF/POM复合材料,研究了BF的添加量、长度对复合材料的力学性能和摩擦学性能的影响,采用扫描电子显微镜观察分析了复合材料的断面形貌和磨痕表面形貌。研究结果表明,BF的加入能有效改善复合材料的力学性能;在一定范围内,复合材料的力学性能会随BF添加量和长度的增加而提高,但增加到一定程度后其力学性能趋于稳定;BF的加入使复合材料的磨损量和摩擦系数都会增加,从而对其摩擦学性能产生不利影响。
语种：
中文
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Strain tuned dehydrogenation thermodynamics of magnesium based hydride: A first principle study
作者：
Zhang, J.* ;Mao, C.;Chen, J.;Long, C. G.;Tang, K.;...
期刊：
计算材料学(英文) ,2015年105:71-74 ISSN：2057-3960
通讯作者：
Zhang, J.
作者机构：
[Zhang, M. J.; Tang, K.; Mao, C.; Long, C. G.; Zhang, J.] Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.;[Zhang, J.] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Peoples R China.;[Chen, J.; Zhang, J.] Changsha Univ Sci & Technol, Coll Hunan Prov, Key Lab Efficient & Clean Energy Utilizat, Changsha 410114, Hunan, Peoples R China.;[Peng, P.] Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Zhang, J.] C;Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.
关键词：
Dehydrogenation thermodynamics;Electronic structure;First-principles calculations;Lattice strain;Magnesium based hydride
摘要：
To improve the dehydrogenation thermodynamics of magnesium based hydride, i.e. MgH2, it is essential to weaken its structural stability. From density functional theory calculations, we show that the crystal structure and dehydrogenation thermodynamics of MgH2 are sensitive to the applied lattice strain. The metastable tetragonal and even orthorhombic MgH2 phase form upon strain. Meanwhile, the hydrogen desorption enthalpy decreases substantially with increasing strain. Especially, the triaxial tensile strain is more conductive to improve the dehydrogenation thermodynamics of MgH2, which can be attributed to the narrower energy gap of MgH2 induced by triaxial tensile strain relative to uniaxial and biaxial tensile ones. These results prompt a new insight to tune the dehydrogenation thermodynamics of metal hydrides by introducing proper lattice strain. © 2015 Elsevier B.V. All rights reserved.
语种：
英文
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Phase stability, elastic properties and electronic structures of Mg–Y intermetallics from first-principles calculations
作者：
Zhang, J.;Mao, C.;Long, C.G.;Chen, J.;Tang, K.;...
期刊：
镁合金学报(英文) ,2015年3(2):127-133 ISSN：2213-9567
通讯作者：
J. Zhang<&wdkj&>C. Mao
作者机构：
[Mao, C.; Long, C.G.; Tang, K.; Zhang, M.J.] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China;[Chen, J.] Key Laboratory of Efficient and Clean Energy Utilization, College of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China;[Peng, P.] College of Materials Science and Engineering, Hunan University, Changsha 410082, China;[Zhang, J.] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China<&wdkj&>Key Laboratory of Efficient and Clean Energy Utilization, College of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China
通讯机构：
[J. Zhang; C. Mao] K;Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China<&wdkj&>Key Laboratory of Efficient and Clean Energy Utilization, College of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China<&wdkj&>Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China
关键词：
Magnesium alloys;Intermetallics;Phase stability;Elastic properties;Electronic structure
摘要：
The phase stability, elastic properties and electronic structures of three typical Mg-Y intermetallics including Mg 24 Y 5 , Mg 2 Y and MgY are systematically investigated using first-principles calculations based on density functional theory. The optimized structural parameters including lattice constants and atomic coordinates are in good agreement with experimental values. The calculated cohesive energies and formation enthalpies show that either phase stability or alloying ability of the three intermetallics is gradually enhanced with increasing Y content. The single-crystal elastic constants C ij of Mg-Y intermetallics are also calculated, and the bulk modulus B, shear modulus G, Young's modulus E, Poisson ratio v and anisotropy factor A of polycrystalline materials are derived. It is suggested that the resistances to volume and shear deformation as well as the stiffness of the three intermetallics are raised with increasing Y content. Besides, these intermetallics all exhibit ductile characteristics, and they are isotropic in compression but anisotropic to a certain degree in shear and stiffness. Comparatively, Mg 24 Y 5 presents a relatively higher ductility, while MgY has a relatively stronger anisotropy in shear and stiffness. Further analysis of electronic structures indicates that the phase stability of Mg-Y intermetallics is closely related with their bonding electrons numbers below Fermi level. Namely, the more bonding electrons number below Fermi level corresponds to the higher structural stability of Mg-Y intermetallics. © 2015 National Engineering Research Center for Magnesium Alloys of China, Chongqing University.
语种：
英文
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Ni、Ti单独/复合掺杂对MgH_2组织结构与解氢性能的影响及机理
作者：
张健;孙立芹;毛聪;龙春光;陈荐
期刊：
材料导报 ,2015年29(22):91-95 ISSN：1005-023X
作者机构：
[张健; 毛聪; 龙春光] 长沙理工大学汽车与机械工程学院;[孙立芹] 湘潭大学材料科学与工程学院;[陈荐] 长沙理工大学能源与动力工程学院
关键词：
镁氢化物;过渡金属;掺杂;组织结构;解氢性能
摘要：
镁氢化物(MgH_2)解氢温度偏高是目前制约其实际应用的主要瓶颈。采用机械球磨方法制备了MgH_2、MgH_2-10%Ni、MgH_2-10%Ti、MgH_2-15%Ni-5%Ti(质量分数)四种不同储氢体系,借助XRD、SEM、DSC等检测手段表征了不同体系的组织结构与解氢性能,并就Ni、Ti单独与复合掺杂对MgH_2解氢性能的影响机理进行了分析。结果表明:Ni、Ti单独掺杂时,较纯MgH_2球磨体系而言,MgH_2颗粒与晶粒尺寸减小且均匀,颗粒团聚现象缓解,初始解氢温度明显降低,其原因在于少量Ni、Ti原子固溶于MgH_2基体,导致其晶格变形、结构稳定性降低,其中,Ni的固溶效果尤为明显;而Ni、Ti复合掺杂时,由于球磨过程中NiTi新相的出现,导致MgH_2颗粒与晶粒细化效果较单独掺杂时有所减弱,然而球磨体系的初始解氢温度较单独掺杂时却进一步降低,实现了Ni、Ti两种元素的协同固溶效应。
语种：
中文
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Adsorption and dissociation of H2O on Al(1 1 1) surface by density functional theory calculation
作者：
Guo, F. Y.;Long, C. G.* ;Zhang, J.;Zhang, Z.;Liu, C. H.;...
期刊：
Applied Surface Science ,2015年324:584-589 ISSN：0169-4332
通讯作者：
Long, C. G.
作者机构：
[Liu, C. H.; Guo, F. Y.; Long, C. G.; Zhang, J.; Zhang, Z.] Changsha Univ Sci & Technol, Inst Automobile & Mech Engn, Changsha 410114, Hunan, Peoples R China.;[Guo, F. Y.; Long, C. G.; Zhang, J.; Zhang, Z.] Chongqing Univ Technol, Minist Educ, Key Lab Mfg & Test Techn Automobile Parts, Chongqing 400054, Peoples R China.;[Guo, F. Y.; Long, C. G.; Zhang, J.; Zhang, Z.] Coll Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.;[Yu, K.] Cent South Univ, Dept Mat Sci & Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Long, C. G.] C;Changsha Univ Sci & Technol, Inst Automobile & Mech Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Adsorption;Al(1 1 1);Density functional theory (DFT);Dissociation
摘要：
Using the first-principles calculations method based on the density functional theory, we systematically study the adsorption behavior of a single molecular H 2 O on a clean and a pre-adsorbed O atom Al(1 1 1) surface, and also its corresponding dissociation reactions. The equilibrium configuration on top, bridge, and hollow (fcc and hcp) site were determined by relaxation of the system relaxation. The adsorptions of H 2 O, OH and H on top sites are favorable on the Al(1 1 1) surface, while that of O on the hollow (fcc) site is preferred. The results show that the hydrogen atom dissociating from H 2 O needs a 248.32 kJ/mol of energy on clean Al(1 1 1) surface, while the dissociating energy decreases to 128.53 kJ/mol with the aid of the O absorption. On the other hand, these phenomena indicate that the dehydrogenated reaction energy barrier of the pre-adsorbed O on metal surface is lower than that of on a clean one, because O can promote the dehydrogenation of H 2 O. © 2014 Elsevier B.V. All rights reserved.
语种：
英文
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Influences and mechanisms of graphene-doping on dehydrogenation properties of MgH2: Experimental and first-principles studies
作者：
Zhang, J.* ;Yu, X. F.;Mao, C.;Long, C. G.;Chen, J.;...
期刊：
Energy ,2015年89:957-964 ISSN：0360-5442
通讯作者：
Zhang, J.
作者机构：
[Yu, X. F.; Mao, C.; Long, C. G.; Zhang, J.] Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.;[Zhang, J.] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Chen, J.; Zhang, J.] Changsha Univ Sci & Technol, Coll Hunan Prov, Key Lab Efficient & Clean Energy Utilizat, Changsha 410114, Hunan, Peoples R China.;[Zhou, D. W.] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Zhang, J.] C;Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.
关键词：
Dehydrogenation properties;Doping;First-principles calculations;Graphene;MgH2
摘要：
Using experimental and first-principles calculations methods, a systematic investigation was performed on the dehydrogenation properties and mechanisms of MgH2-10 wt%G (graphene) composites acquired by ball milling. It was found that the doping of G played a vital catalytic role in improving the dehydrogenation properties of MgH2. SEM (scanning electron microscopy) observations revealed that G sheets were dispersedly embedded in MgH2 particles, which effectively inhibited the agglomerating of MgH2 particles during ball milling. XRD (X-ray diffraction) analyses showed that no new phases formed due to the immiscibility between MgH2(Mg) and G. DSC (Differential Scanning Calorimetry) and DTG (Differential Thermal Gravity) measurements indicated the initial dehydrogenation temperatures of MgH2-G composites were decreased and their dehydrogenation rate were also increased relative to pure-milled MgH2. The mechanisms analyses based on first-principles calculations suggested that the improved dehydrogenation properties of MgH2-G composites should be ascribed to the reduced dehydrogenation enthalpy and dehydrogenation activation energy of MgH2 upon the catalytic role of G. © 2015 Elsevier Ltd.
语种：
英文
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基于生命内涵的产品形态仿生设计探究
作者：
谢炜;程海峰;匡加才;楚增勇;陈朝辉;...
期刊：
包装工程 ,2014年35(18):34-38 ISSN：1001-3563
作者机构：
[谢炜; 龙春光] 长沙理工大学汽车与机械工程学院;[程海峰; 楚增勇; 陈朝辉] 国防科学技术大学;[匡加才] 长沙理工大学材料科学与工程研究所
关键词：
自我意识;生命;运动;产品形态仿生
摘要：
目的探究产品形态仿生设计的生命内涵从而更好地指导产品形态仿生设计。方法以自我意识为线索引出产品形态仿生设计的生命通感,深入至产品形态仿生设计的生命内涵并对其进行解读。结论生命内涵是运动与发展的,具象形态仿生和抽象形态仿生在表达生命内涵时有所差异。
语种：
中文
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