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Construction of bio-functional Mg/HA composite layered coating for orthopedic application

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Science China(Technological Sciences) 2021年第11期64卷 2541-2550页

作者： WAN Peng YAN XuDong LI Mei zhao mingchun ZHANG Yu YANG Ke School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Central South UniversityChangsha 410083China Research Center of Medical Sciences Guangdong Provincial People s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China

Magnesium was considered as a revolutionary biodegradable implant material for orthopedic application. Concerning the weakness of intrinsic strength and corrosion behavior, a novel strategy of Mg/metal hybrid system was proposed for extension of orthopedic application, especially at load-bearing site. In this work, an Mg and HA composite layered coating was constructed on titanium by means of chemical conversion and vapor deposition. The HA transition interlayer was introduced to enhance the bonding between Mg film and Ti substrate. Compared with the bare Mg coating, the Mg/HA coating presented good interface bonding, which avoided the occurrence of Mg film peeling off from the substrate. The Mg/HA coating showed a uniform degradation and kept integrity after immersion of 14 d. The Mg ions release by degradation played a crucial role in osteopromotion and antibacterial effect. Incubation of MC3T3-E1 osteoblasts with the Mg/HA coating showed significant promotion on osteogenic differentiation according to ALP activity and Alizarin Red staining assays. Meanwhile the degradation of Mg exhibited strong suppression of bacteria proliferation. It was believed that this novel Mg/HA composite layered coating could be potentially applied in further development of bio-functional hybrid orthopedic implants.

关键词： magnesium HA composite layered coating titanium orthopedic bio-function

Designing a high Si reduced activation ferritic/martensitic steel for nuclear power generation by using Calphad method

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Journal of Materials Science & Technology 2019年第3期35卷 266-274页

作者： Chao Liu Quanqiang Shi Wei Yan Chunguang Shen Ke Yang Yiyin Shan mingchun zhao Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences School of Material Science and Engineering Central South University The State Key Laboratory of Rolling and Automation Northeastern University

A high Si reduced activation ferritic/martensitic(RAFM) steel for nuclear structure application is successfully designed by using Calphad method. The main designed chemical composition is C 0.18–0.22%, Cr10.0–10.5%, W 1.0–1.5%, Si 1.0–1.3%, V+Ta 0.30–0.45%, and Fe in balance. High Si design brings excellent corrosion resistance, while low activation is advantageous in the nuclear waste processing. The experimental results indicate that the newly designed high Si RAFM steel had full martensitic structure and uniformly distributed fine second phase particles, and exhibited excellent mechanical properties and corrosion resistance. Compared to the P91 steel, this new RAFM steel designed by Calphad method is expected to be a promising candidate used in nuclear power generation, which also provides a new and effective approach to the development of RAFM steel for nuclear application.

关键词： Ferritic/martensitic steel Alloy design Calphad method Reduced activation High silicon

Microstructure, biodegradation, antibacterial and mechanical properties of ZK60-Cu alloys prepared by selective laser melting technique

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Journal of Materials Science & Technology 2018年第10期34卷 1944-1952页

作者： Cijun Shuai Long Liu mingchun zhao Pei Feng Youwen Yang Wang Guo Chengde Gao Fulai Yuan State Key Laboratory of High Performance Complex Manufacturing College of Mechanical and Electrical Engineering Central South University Changsha410083 China Jiangxi University of Science and Technology Ganzhou 341000 China Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan Province Changsha 410008 China School of Material Science and Engineering Central South University Changsha 410083 China Health Management Center Xiangya Hospital Central South University Changsha 410008 China

Magnesium （Mg） alloys are receiving increasing attention for body implants owing to their good bio- compatibility and biodegradability. However, they often suffer from bacterial infections on account of their insufficient antibacterial ability. In this study, ZK60-xCu （x = O, 0.2, 0.4, 0.6 and 0.8 wt%） alloys were prepared by selective laser melting （SLM） with alloying copper （Cu） to enhance their antibacterial ability. Results showed that ZK60-Cu alloys exhibited strong antibacterial ability due to combination of release of Cu ions and alkaline environment which could kill bacteria by destroying cellular membrane structure, denaturing enzymes and inhibiting deoxyribonucleic acid （DNA） replication. In addition, their compres- sive strength increased due to grain refinement and uniformly dispersing of short-bar shaped MgZnCu phases. Moreover, ZK60-Cu alloys also exhibited good cytocompatibility. In summary, ZK60-Cu alloys with antibacterial ability may be Dromising implants for biomedical anDlications.

关键词： Magnesium alloys Copper Antibacterial ability Cytocompatibility Mechanical properties

Microstructure evolution and texture tailoring of reduced graphene oxide reinforced Zn scaffold

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Bioactive Materials 2021年第5期6卷 1230-1241页

作者： Youwen Yang Yun Cheng Shuping Peng Liang Xu Chongxian He Fangwei Qi mingchun zhao Cijun Shuai Institute of Bioadditive Manufacturing Jiangxi University of Science and TechnologyNanchang330013China NHC Key Laboratory of Carcinogenesis School of Basic Medical ScienceCentral South UniversityChangshaHunan410013China School of Energy and Machinery Engineering Jiangxi University of Science and TechnologyNanchang330013China School of Materials and Engineering Central South UniversityChangsha410083China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha410083China Shenzhen Institute of Information Technology Shenzhen518172China

Zinc(Zn)possesses desirable degradability and favorable biocompatibility,thus being recognized as a promising bone implant ***,the insufficient mechanical performance limits its further clinical *** this study,reduced graphene oxide(RGO)was used as reinforcement in Zn scaffold fabricated via laser additive *** showed that the homogeneously dispersed RGO simultaneously enhanced the strength and ductility of Zn *** one hand,the enhanced strength was ascribed to(i)the grain refinement caused by the pinning effect of RGO,(ii)the efficient load shift due to the huge specific surface area of RGO and the favorable interface bonding between RGO and Zn matrix,and(iii)the Orowan strengthening by the homogeneously distributed *** the other hand,the improved ductility was owing to the RGO-induced random orientation of grain with texture index reducing from 20.5 to 7.3,which activated more slip systems and provided more space to accommodate ***,the cell test confirmed that RGO promoted cell growth and *** study demonstrated the great potential of RGO in tailoring the mechanical performance and cell behavior of Zn scaffold for bone repair.

关键词： Zn scaffold RGO Laser additive manufacturing Mechanical performance Cell behavior

基于循环荷载损伤定量控制的岩石CWFS改进模型研究

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岩石力学与工程学报 2024年第4期43卷 781-796页

作者：苗胜军刘泽京梁明纯赵子岐北京科技大学城市地下空间工程北京市重点实验室北京100083 北京科技大学土木与资源工程学院北京100083

黏聚力强度弱化–摩擦力强度强化(CWFS)模型形式简洁且参数物理意义明确,但模型准确度和适用性欠佳。开展花岗岩(致密结晶硬岩)和粉砂岩(多孔弱胶结岩)的三轴分级循环加卸载损伤控制试验,对传统CWFS模型进行黏聚力和内摩擦角方程、剪胀... 详细信息

黏聚力强度弱化–摩擦力强度强化(CWFS)模型形式简洁且参数物理意义明确,但模型准确度和适用性欠佳。开展花岗岩(致密结晶硬岩)和粉砂岩(多孔弱胶结岩)的三轴分级循环加卸载损伤控制试验,对传统CWFS模型进行黏聚力和内摩擦角方程、剪胀角方程、横纵应变比方程3个方面的改进。首先,优化模型应力水平定量表征点并统一塑性参数以准确获取模型参数定量结果;而后,适应岩石试验黏聚力弱化和摩擦力先强化后弱化的特征结果,引入强化和弱化控制系数,构建非线性黏聚力和内摩擦角方程;最后,对应屈服阶段的非线性剪胀和屈服前弹性阶段的显著非线性横向变形,分别建立非线性剪胀角方程和横纵应变比方程。适用性验证结果表明,改进后的CWFS模型可准确适用于试验花岗岩和粉砂岩,亦可准确适用于北山花岗岩和砂岩,能够合理地描述岩石全应力–应变过程中的应变软化、剪胀扩容和弹塑性应变演化规律,较传统CWFS模型准确度和适用性均有显著提高。

关键词：岩石力学 CWFS模型黏聚力强度摩擦力强度非线性剪胀横纵应变比

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Discussion on the Relationship between Different Earthquake Magnitude Scales and the Effect of Seismic Station Sites on Magnitude Estimation

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Earthquake Research in China 2008年第1期22卷 24-30页

作者： Zhang Hongzhi Diao Guiling zhao mingchun Wang Qincai Zhang Xiao Huang Yuan Institute of Geophysics CEA Beijing 100081 China Earthquake Administration of Hebei Province Shijiazhuang 050021 China Earthquake Administration of Tangshan City Tangshan 063000 China）

Based on the earthquake catalog reported by the Chinese digital seismic network in recent years,we select the earthquakes with both surface wave magnitude and local magnitude and fit them into a relationship between the two *** systematic difference is found from the formula which has been used for 30 *** of a large dynamic range and wide frequency range of the current digital observation system,in addition to a larger number of stations and earthquakes being used compared to before,the relation obtained in this paper seems more *** calculation shows that there is no significant difference before and after magnitude conversion so we suggest the abandonment of magnitude *** site response of a station consists of amplification at different *** amplification is equal to about 1 and changes little with frequency at stations located on basement rock,and it is greater than 1 at low frequency ranges and less than 1 at high frequency ranges at stations located on sediment *** difference between magnitudes from single station located on sediment layer and the average magnitude from the whole network increases from negative to positive with *** seems that there is no fixed station correction factor and the station correction method does not work to improve the accuracy and magnitude estimates.

关键词：震级地震波活动层探测方法

碳锰钢中亚微米和微米尺寸铁素体晶粒的长大行为

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材料研究学报 2008年第2期22卷 152-156页

作者：胡其平赵颖超赵明纯花村年裕中南大学材料科学与工程学院长沙410083 日本国立材料研究所日本筑波3050047

碳锰钢中有亚微米和微米两种晶粒尺寸的铁素体,在亚临界时效热处理中具有不同的晶粒长大行为.亚微米尺寸的铁素体在亚临界时效热处理中逐渐长大,材料的硬度逐渐降低;与亚微米尺寸的铁索体不同,微米尺寸的铁索体在亚临界热处理中具有很... 详细信息

碳锰钢中有亚微米和微米两种晶粒尺寸的铁素体,在亚临界时效热处理中具有不同的晶粒长大行为.亚微米尺寸的铁素体在亚临界时效热处理中逐渐长大,材料的硬度逐渐降低;与亚微米尺寸的铁索体不同,微米尺寸的铁索体在亚临界热处理中具有很高的稳定性,晶粒尺寸和材料的硬度基本保持不变.铁索体晶粒的长大行为与晶粒的表面能和晶粒中的第二相有关.

关键词：金属材料碳锰钢时效晶粒长大硬度亚微米尺寸铁素体

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当前失地农民存在的问题及对策

安徽农学通报 2008年第20期14卷 4-5,10页

作者：赵明春山东省滨州市滨城区农业局山东滨州256617

针对在推进农村城市化、城市现代化的进程中失地农民存在的一系列问题,本文从多方面分析原因,结合现在政府政策和滨城区解决失地农民问题的实例,从补偿标准、建立保障机制和集体资产管理、自主创业等方面提出了解决问题的思路。

关键词：失地农民安置补偿保障

大气等离子喷涂CuAl/hBN涂层的高温磨损性能

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电镀与涂饰 2022年第12期41卷 844-851页

作者：闫希彦杨焜曾克里邓春明邓畅光赵明纯中南大学湖南长沙410083 广东省科学院新材料研究所现代材料表面工程技术国家工程实验室广东省现代表面工程技术重点实验室广东广州510650

利用大气等离子喷涂工艺制备了铝−六方氮化硼(Al/hBN)和铜铝−六方氮化硼(CuAl/hBN)可磨耗封严涂层,表征了两种涂层的形貌、物相、硬度、结合强度、hBN烧损及450°C下的磨损性能。结果表明,相较于Al/hBN涂层,CuAl/hBN涂层的hBN烧损比例... 详细信息

利用大气等离子喷涂工艺制备了铝−六方氮化硼(Al/hBN)和铜铝−六方氮化硼(CuAl/hBN)可磨耗封严涂层,表征了两种涂层的形貌、物相、硬度、结合强度、hBN烧损及450°C下的磨损性能。结果表明,相较于Al/hBN涂层,CuAl/hBN涂层的hBN烧损比例降低了20.2%,hBN相与孔隙更加细小及分布均匀,洛氏硬度小幅度升高且在不同部位上的差异更小,结合强度虽降低了2.67 MPa,但仍符合工程应用标准。在高温磨损试验中,CuAl/hBN涂层的质量损失不到Al/hBN的1/10,Al/hBN涂层的磨损机制以黏着磨损为主,而CuAl/hBN涂层以磨粒磨损为主,同时伴有少量的氧化磨损。CuAl/hBN涂层的摩擦副质量略有减小,其表面粘附的涂层极少;Al/hBN涂层的摩擦副则因涂层转移而导致质量增加。在Al/hBN可磨耗封严涂层中添加枝晶Cu能够明显抑制喷涂过程中非金属相的烧损,令非金属相的含量及分布得到明显改善,从而提高涂层的硬度及耐磨耗性能,以及与对磨部件的摩擦相容性。

关键词：可磨耗封严涂层铜铝六方氮化硼大气等离子喷涂摩擦磨损行为

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