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高职学生新媒体能力培育模型构建与实践探索

九江职业技术学院学报 2024年第2期 82-87页

作者：郭好春朱宝宏杭州科技职业技术学院浙江杭州311402

数字经济时代,不断迭代的新媒体理念与技术引爆了营销新动能,职业人才的新媒体能力成为各行业从业人员重要的职业能力。本文将陶行知教育思想应用于新媒体教学实践,构建了高职学生新媒体能力“三元三域”培育模型。该模型的核心为“教... 详细信息

数字经济时代,不断迭代的新媒体理念与技术引爆了营销新动能,职业人才的新媒体能力成为各行业从业人员重要的职业能力。本文将陶行知教育思想应用于新媒体教学实践,构建了高职学生新媒体能力“三元三域”培育模型。该模型的核心为“教学做”三元合一的教学范式、“行知行”三重递进的认知逻辑、“生活学校社会”三域融通的教学场景。

关键词：高职学生新媒体能力陶行知教育思想培育模型

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典型轴瓦的组织和性能分析

轴承 2024年第10期 107-114页

作者：吴帅帅孙健郭胜利辛琦朱宝宏有研工程技术研究院有限公司北京101407 中国有研科技集团有限公司北京100088 重庆跃进机械厂有限公司重庆402160

采用SEM,EPMA,EBSD等设备分析了某典型柴油内燃机主轴用进口轴瓦的显微组织及性能。结果表明:主轴上瓦由钢背、Al-Zn合金层、镍栅、Pb-Sn-Cu合金组成,主轴下瓦和连杆瓦由钢背、Cu-Pb-Sn合金层、镍栅、溅射AlSn20Cu层组成;采用纳米压痕... 详细信息

采用SEM,EPMA,EBSD等设备分析了某典型柴油内燃机主轴用进口轴瓦的显微组织及性能。结果表明:主轴上瓦由钢背、Al-Zn合金层、镍栅、Pb-Sn-Cu合金组成,主轴下瓦和连杆瓦由钢背、Cu-Pb-Sn合金层、镍栅、溅射AlSn20Cu层组成;采用纳米压痕仪测得主轴上、下瓦、连杆瓦镀层硬度分别为0.212,1.223,1.313 GPa;主轴上瓦合金层组织为颗粒状Pb,Si分布于等轴状Al晶粒中,主轴下瓦、连杆瓦合金层组织为树枝状Pb相分布于柱状Cu晶粒中;主轴上、下瓦和连杆瓦的钢背均为低碳钢,组织由铁素体和珠光体组成,但组织形貌不同,均存在D类氧化夹杂物。

关键词：滑动轴承内燃机主轴轴瓦复合材料成分分析硬度

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MW级大储能量飞轮轴系结构力学及动力学研究

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储能科学与技术 2024年第5期13卷 1542-1550页

作者：胡东旭朱少飞魏晓钢崔亚东祝保红戴兴建李文陈海生中国科学院工程热物理研究所北京100190 中国科学院大学北京100049 中核汇能内蒙古能源有限公司内蒙古呼和浩特010010 中海油新能源二连浩特风电有限公司内蒙古二连浩特011199 北京泓慧国际能源技术发展有限公司北京101300

当前,对于高功率大储能量飞轮储能系统的仿真和实验研究还不够充分,本工作主要针对MW/100 MJ级飞轮储能样机展开。比较分析了内置式和表贴式两种结构飞轮电机转子的结构力学,比较了不同动平衡块材质对应力及形变的影响,并开展了轴系的... 详细信息

当前,对于高功率大储能量飞轮储能系统的仿真和实验研究还不够充分,本工作主要针对MW/100 MJ级飞轮储能样机展开。比较分析了内置式和表贴式两种结构飞轮电机转子的结构力学,比较了不同动平衡块材质对应力及形变的影响,并开展了轴系的动力学特性分析。对飞轮样机开展了实验测试,验证了系统的稳定性。数值计算结果表明,表贴式结构形式可以使电机硅钢片应力显著降低,但是通常这种结构需要在硅钢片外缠绕碳纤维加强层,以确保运行时磁钢不会因为离心力与硅钢片发生分离。动平衡块材质为不锈钢时的应力值相较于动平衡块为铝合金时提高了45%以上。对轴系进行了动力学特性分析,在工作转速下存在着1300 r/min和4200 r/min两个刚性振型,分别为平动和锥动。测试运行中,飞轮轴系在1300 r/min出现振动峰值,证明了数值仿真计算的准确性。但是数值仿真中的4200 r/min临界转速(锥动)在实际运行中并未出现明显峰值,在本工作的轴系结构中,相较于锥动,平动振型更容易被激发。

关键词：飞轮电机数值仿真

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Effects of the two-step ageing treatment on the microstructure and properties of 7B04 alloy pre-stretched thick plates

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Rare Metals 2007年第3期26卷 193-199页

作者： LI Zhihui XIONG Baiqing ZHANG Yong ＇an zhu baohong WANG Feng LIU Hongwei State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing 100088 China

The effects of the two-step ageing parameters （temperature and time） on the mechanical properties and electrical conductivity of 7B04 （A1-Zn-Mg-Cu） pre-stretched thick plates were studied. The results reveal that the initial T1 ageing contributes a major increase of the tensile strength, and the 0.2% proof stress value reaches 482 MPa after ageing for 7 h at 115℃. Behavioral differences in the tensile properties of the alloy after the two-step ageing treatment were less with the first-step ageing at 115~C for different time periods （7, 14, and 21 h）. The effects of the second ageing parameters on the properties and microstructure of the 7B04 alloy were remarkable. TEM analysis of the samples aged at Temper I （7 h at 115℃ ＋ 12 h at 160℃） and Temper II （7 h at 115℃ ＋ 16 h at 165℃） indicates that two kinds of phases, i.e. 11＇ and 11 phases, precipitate from the matrix and efficiently improve the tensile strength of the alloy, and the grain boundary precipitates are coarse and discrete. There are obvious precipitate free zones （PFZs） along the grain boundary in the microstructure of the alloy after the two-step ageing treatment.

关键词： 7B04 alloy two-step ageing mechanical properties electrical conductivity microstructure

Ageing behavior of an Al-Zn-Mg-Cu alloy pre-stretched thick plate

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Journal of University of Science and Technology Beijing 2007年第3期14卷 246-250页

作者： Zhihui Li Baiqing Xiong Yongan Zhang baohong zhu Feng Wang Hongwei Liu State Key Laboratory for Fabrication and Processing of Non-ferrous Metals General Research Institute for Non-ferrous Metals Beijing 100088 China

The ageing behavior of a pre-stretched thick plate of Al-Zn-Mg-Cu alloy was systemically studied including one-step ageing, two-step ageing, and retrogression and reageing treatment （RRA）. One-step ageing of the alloy resulted in peak ultimate tensile strengths of 595 and 575 MPa after 22 and 6 h at 120 and 135°C, respectively. The strengthening phase in peak aged （T6 temper） alloy contained GP zones and the η′ phase predominantly. After two-step ageing, the electrical conductivity was increased markedly, but the pre-stretched thick plate sacrificed a great loss of strength. RRA treatment provided a method for maintaining the strength close to that obtained by T6 temper and for obtaining the high electrical conductivity close to that obtained by T7 temper; the ultimate tensile strength and electrical conductivity were 583 MPa and 21.0 MS/m, respectively. TEM analysis of T7 and RRA specimens revealed two types of precipitates that contributed to age strengthening i.e. the η′ and η phases.

关键词： Al-Zn-Mg-Cu alloy pre-stretched thick plate ageing tensile properties precipitation

Effect of P/M value on the preforms and microstructures of spray formed 70Si30Al alloy

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Journal of University of Science and Technology Beijing 2007年第2期14卷 141-145页

作者： Yanguang Wei Baiqing Xiong Yongan Zhang Hongwei Liu Feng Wang baohong zhu State Key Laboratory for Fabrication ＆ Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

A novel 70Si30Al alloy was prepared by the spray forming process for electronic packaging materials. The effect of the ratio of atomization pressure to metal melt mass flux rate （P/M） on the preforms and microstructures of the spray-deposited 70Si30Al alloy was studied. The results indicate that the PIM value has a considerable influence on the formation of the preforms and the optimal value is in the range of 0.209-0.231 MPa/（***^-1）. The microstructure of the spray formed 70Si30AI alloy is fine and homogenous. The primary silicon phases distributing in the aluminum matrix evenly are fine and irregular. The aluminum matrix is divided into two groups： supersaturated α-Al phase or α-Al phase and Al-Si pseudoeutectic phase or Al-Si eutectic phase.

关键词： 70Si30Al alloy spray forming atomization pressure mass flux rate microstructure

Age-hardening characteristic of an Al-Zn-Mg-Cu alloy produced by spray deposition

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Rare Metals 2007年第2期26卷 163-168页

作者： WANG Feng XIONG Baiqing ZHANG Yongan zhu baohong LIU Hongwei ZHANG Zhihui WANG Zixing State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

Al-10.8Zn-2.8Mg-1.9Cu alloy was synthesized by spray atomization and deposition technique. GP zones and age-hardening process in the alloy were investigated using high-resolution electron microscopy （HREM）, selected area diffraction （SAD）, and differential scanning calorimetry （DSC） analysis. The results indicated that spray deposition process accelerated the aging kinetics of the alloy at an aging temperature of 120℃, thereby reducing the peak aging time to 16 h. GPⅠ and GPⅡ are the two types of zones that are major precipitates for the alloy under peak-aged condition. The precipitation sequence for the alloy is also discussed.

关键词： aluminium alloy precipitation GP zone spray deposition

Simultaneously Enhanced Thermal and Mechanical Properties of ZK60 Alloy Reinforced by Oriented Graphene Nanoplatelets

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Acta Metallurgica Sinica(English Letters) 2023年第12期36卷 1999-2012页

作者： baohong zhu Xian Du Fanjing Meng Xuefeng Wu Ke Liu Shubo Li Zhaohui Wang Wenbo Du Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100124China

The lamellar and orientational characteristics of graphene nanoplatelets(GNPs)are crucial for reinforcing metal matrix composites,particularly in terms of their thermal *** kinds of GNPs with plane sizes of 6µm and 80µm were respectively used as reinforcements in ZK60 alloy by powder *** oriented distribution of GNPs in the matrix was obtained using a double-pass hot extrusion process,i.e.,a stepped extrusion with two consecutive extrusion ratios(10:1 and 16:1).Reinforced with 0.05 wt%oriented GNPs(80µm),the composite exhibited a tensile yield strength of 257 MPa,ultimate tensile strength of 342 MPa,elongation of 24.7%,and notably enhanced thermal conductivity of 128.3 W(mK)−1 even with refined grain size compared to the ZK60 *** oriented GNPs in the matrix create a favorable path for efficient load and heat transfer,leading to the simultaneously enhancement of mechanical and thermal properties of the GNPs/ZK60 *** work is expected to broaden the application potential of GNPs as highly efficient reinforcements and provide a practical method for fabricating metal matrix composites.

关键词： Graphene Magnesium Orientation Thermal properties Mechanical properties

Deformation mechanism of the spray formed 70Si30Al alloy during hot compression

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Rare Metals 2007年第1期26卷 56-61页

作者： WEI Yanguang XIONG Baiqing ZHANG Yong＇an LIU Hongwei WANG Feng zhu baohong State Key Laboratory for Fabrication ＆ Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing 100088 China

The deformation mechanism of the spray formed 70Si30Al alloy was studied by hot compression on a Gleeble-1500 test machine. It is shown that hot deformation of the spray formed 70Si30Al alloy is achieved by liquid flow due to isostatic pressure and movement of solid particles due to shear force. Deformation condition depends on the nucleation rate and closure rate of the cavities. The flow stress slightly varies when the difference between the nucleation rate and closure rate of the cavities is small; however, it decreases when the nucleation rate of the cavities is greater than the closure rate of the cavities.

关键词： 70Si30Al alloy spray forming hot compression deformation mechanism