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Fracture behavior of 304 stainless steel coatings by cold gas dynamic spray

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Acta Metallurgica Sinica(English Letters) 2011年第3期24卷 249-254页

作者： Wei HAN Xianming MENG Jie ZHAO junbao zhang School of Materials Science and Engineering Dalian University of Technology Dalian 116085 China Baosteel Research Institute Baoshan Iron & Steel Co. Ltd. Shanghai 201900 China

304 stainless steel coating was deposited on the Interstitial-Free steel substrate by cold gas dynamic spraying （CGDS）. Three-point bending test of the cold sprayed 304 stainless steel coating was tested by SHIMADZU electro-hydraulic servo-controlled fatigue testing machine and the fracture morphology was examined by scanning electron microscopy. The results showed that the fracture behavior of the cold sprayed 304 stainless steel coating was brittleness fracture. The crack in the coating occurred in the interfaces between particles and the crack extended to the internal of the coating with the increase of the load. When the crack has extended to the combination interface between coating and substrate, the crack extended to the two sides. The microstructure and mechanical property of the cold sprayed 304 stainless steel coating have been optimized after heat treatment.

关键词： Cold gas dynamic spraying 304 stainless steel coating Three- point bending test Fracture behavior Heat treatment

Influence of annealing treatment on microstructure and properties of cold sprayed stainless steel coatings

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Acta Metallurgica Sinica(English Letters) 2011年第2期24卷 92-100页

作者： Xianming MENG junbao zhang Jie ZHAO Wei HAN Yongli LIANG School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China Baosteel Research Institute Baoshan Iron & Steel Co. Ltd. Shanghai 201900 China

304 stainless steel coatings had been deposited on carbon-steel substrate by cold spray technique, vacuum annealing treatment was applied to the coatings with different temperatures, and the influence of annealing treatment on the microstructure and electrochemical behavior of the coatings in 3.5% NaCl were analyzed. The results indicated that, the cold sprayed coating was constituted by the flattened particles, and the interfaces were clearly observed between the deposited particles. It was also found that annealing treatment led to the recovery and recrystallization of the elongated grains in the as-sprayed coatings with the increase of annealing temperature. When the annealing temperature achieved to 950 ？ C, the interface of particles was disappeared and the coating s structure was made of new recrystallization austenite grains. Annealing treatment increased the potential volts, and reduced the corrosion rate with the increase of annealing temperature. The electrical corrosion morphology indicated that, the corrosion was firstly at the distortion area and the crevice corrosion mechanism played an important part. Based on these results, processes active during annealing treatment are kinetically dependent and strongly influenced by the annealing treatment temperature.

关键词： Cold spray 304 stainless steel coating Annealing treatment Corrosion behavior

Microstructure and nano-mechanical property of cold spray Co-base refractory alloy coating

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Acta Metallurgica Sinica(English Letters) 2011年第3期24卷 190-194页

作者： Vongli LIANG Bi SHI Xiaoping YANG junbao zhang Xianming MENG Advanced Technology Institute Baosteel Technology Center Baoshan Iron & Steel Co. Shanghai 201900 China School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China

Co-base refractory alloy coating was prepared on carbon steel substrate by cold spray technology; microstructure and nano-mechenieal property were examined by scanning electron microscope （SEM） and nano indenter individually. The results showed that about 250 μm Co-base refractory alloy coating could be deposited o11 steel substrate by cold spray technique, interface between coating and substrate was combined well, and the refractory alloy particle had a significant plastic deformation during deposition process; mixing Ni powders into Co-base refractory alloy powders could increase the density and decrease the nano-hardness of coating, the nano-hardness and elastic modulus of refractory alloy coating was higher than 6 GPa and 160 GPa, respectively.

关键词： Cold spray Co-base refractory alloy Microstructure Nano-mechanical property

三代核电反应堆压力容器低合金钢焊缝性能对比分析

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压力容器 2024年第2期41卷 1-6页

作者：梅乐张俊宝王永东黄逸峰王秉熙郑明光上海核工程研究设计院股份有限公司上海200233

通过模拟国内三代核电压水堆反应堆压力容器环焊缝,分别采用国产焊接材料和进口焊接材料,在焊接工艺性能、焊缝金属化学成分、拉伸、冲击韧性、落锤和低周疲劳试验等方面进行了对比分析。结果表明,国产和进口焊接材料的焊接工艺性能和... 详细信息

通过模拟国内三代核电压水堆反应堆压力容器环焊缝,分别采用国产焊接材料和进口焊接材料,在焊接工艺性能、焊缝金属化学成分、拉伸、冲击韧性、落锤和低周疲劳试验等方面进行了对比分析。结果表明,国产和进口焊接材料的焊接工艺性能和焊缝金属力学性能均相当;焊接试件不同厚度取样位置的焊缝金属-28.3℃冲击吸收能量平均值都大于90 J,有较大的设计裕量。该国产焊接材料已应用于国内某三代核电机组反应堆压力容器,为进一步推广应用提供技术支撑。

关键词：反应堆压力容器 SA-508 Gr.3 Cl.1钢国产焊材焊缝性能

光伏现场基于5G NR-U任务卸载的边缘云组网方法

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电力信息与通信技术 2024年第5期22卷 70-76页

作者：杨玲张军保王智博景春峰国网新疆电力有限公司巴州供电公司新疆维吾尔自治区巴州841000 南京南瑞信息通信科技有限公司江苏省南京市210003

为处理分布式光伏发电设备接入电力系统所产生的大量计算任务,满足5G用户设备的低时延需求,文章提出了一种光伏现场基于5G空中接口(5G new radio in unlicensed spectrum,5G NR-U)任务卸载的异构边缘云组网架构,通过将光伏计算任务分布... 详细信息

为处理分布式光伏发电设备接入电力系统所产生的大量计算任务,满足5G用户设备的低时延需求,文章提出了一种光伏现场基于5G空中接口(5G new radio in unlicensed spectrum,5G NR-U)任务卸载的异构边缘云组网架构,通过将光伏计算任务分布式分配给异构的移动边缘计算(mobile edge computing,MEC),建立多用户多任务场景下系统时延和终端能耗最小化为目标的边缘云任务卸载模型,进而提出了一种基于人工免疫算法的多任务卸载策略。实验结果表明,提出的方案有效降低了光伏现场计算任务的综合代价,为5GNR-U时间敏感业务提供确定性通信保障。

关键词：异构边缘云边云联合调度光伏现场 5G NR-U 时间敏感业务

维普期刊数据库博看期刊

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复杂厚板钢结构焊接裂纹分析及对策

焊接 2024年第5期 75-80页

作者：朱瑞峰张俊宝吴崇志丛大志上海核工程研究设计院股份有限公司上海200233

在现代发电站结构设计中,通常采用钢结构和钢板-混凝土结构形成主体结构,通过协同作用实现建筑抗震,整个施工过程涉及大量的钢结构焊接工作。大厚板、复杂节点、空间受限等问题导致钢结构焊接出现了冷裂纹和层状撕裂问题,这些问题的起... 详细信息

在现代发电站结构设计中,通常采用钢结构和钢板-混凝土结构形成主体结构,通过协同作用实现建筑抗震,整个施工过程涉及大量的钢结构焊接工作。大厚板、复杂节点、空间受限等问题导致钢结构焊接出现了冷裂纹和层状撕裂问题,这些问题的起因既有预热、后热、焊接热输入控制等焊接工艺本身的问题,也有焊接接头布置及坡口设计不当的问题。该研究针对这些问题的起因进行了深入分析,采取了针对性措施改进加热方式、控制焊接热输入和优化焊接接头,解决了上述焊接裂纹问题。该研究积累的经验和提出的改进措施不仅对发电站的复杂厚板钢结构焊接有直接指导作用,对其他行业钢结构的焊接也有一定的借鉴作用。

关键词：钢结构焊接冷裂纹层状撕裂对策

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特厚煤层综放工作面顶板破断及围岩应力分析

煤矿机械 2024年第9期45卷 68-70页

作者：张君宝刘增辉吴子扬冉永府安徽理工大学矿业工程学院安徽淮南232001

针对特厚煤层综放工作面矿压显现强、顶板治理的难题,以梨园河煤矿51104综放工作面为背景,通过理论和数值仿真,对工作面推进过程中的顶板破断特性及围岩应力演化进行了研究。极限跨距计算求得基本顶初次破断步距为33.7 m;通过FLAC3D软... 详细信息

针对特厚煤层综放工作面矿压显现强、顶板治理的难题,以梨园河煤矿51104综放工作面为背景,通过理论和数值仿真,对工作面推进过程中的顶板破断特性及围岩应力演化进行了研究。极限跨距计算求得基本顶初次破断步距为33.7 m;通过FLAC3D软件分析工作面推进过程中围岩应力规律及塑性区变化,得到基本顶初次破断步距为30~35 m,与理论分析结果相符。

关键词：综放工作面理论分析数值模拟初次破断步距

Synthesis and Ceramic Conversion of Polysiloxazane to Silicon Oxynitride

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Journal of Materials Science & Technology 2001年第1期17卷 3-4页

作者： junbao zhang Tingquan LEI Guangwu WEN and Yu ZHOU School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China Sch. of Mater. Sci. Harbin Inst. of Technol. Harbin 150001 China

Amorphous silicon oxynitride powders have been obtained by pyrolysis of polysiloxazane in a stream of anhydrous NH3 at the temperature up to 1000℃. The polysiloxazane is fabricated from ammonolysis of chloropolysiloxane that is produced by the hydrolysis of silicon tetrachloride. The conversion of polysiloxazane to silicon oxynitride and the structural features of the final powders have also been studied by infrared spectra, elemental composition and X-ray diffraction analysis and SEM observation.

关键词： POLYMERIC PRECURSOR DICHLOROMETHYLSILANE NITRIDATION XEROGELS

Fatigue properties and damage constitutive model of salt rock based on CT scanning

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International Journal of Mining Science and Technology 2024年第2期34卷 245-259页

作者： junbao Wang Xiao Liu Qiang zhang Xinrong Liu Zhanping Song Shijin Feng College of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Lab of Geotechnical and Underground Space Engineering Xi’an 710055China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

To investigate the macroscopic fatigue properties and the mesoscopic pore evolution characteristics of salt rock under cyclic loading,fatigue tests under different upper-limit stresses were carried out on salt rock,and the mesoscopic pore structures of salt rock before and after fatigue tests and under different cycle numbers were measured using CT scanning *** on the test results,the effects of the cycle number and the upper-limit stress on the evolution of cracks,pore morphology,pore number,pore volume,pore size,plane porosity,and volume porosity of salt rock were *** failure path of salt rock specimens under cyclic loading was analyzed using the distribution law of plane *** damage variable of salt rock under cyclic loading was defined on basis of the variation of volume porosity with cycle *** order to describe the fatigue deformation behavior of salt rock under cyclic loading,the nonlinear Burgers damage constitutive model was further *** results show that the model established can better reflect the whole development process of fatigue deformation of salt rock under cyclic loading.

关键词： Salt rock Cyclic loading CT scanning Mesoscopic pore evolution Constitutive model