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碳化硅复合材料包壳燃料棒在LOCA事故中的特性研究
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作者 尚新渊 张爱民 《核技术》 CAS CSCD 北大核心 2019年第8期62-66,共5页
碳化硅复合材料具有热膨胀系数低、中子吸收截面低、抵抗热冲击、高温下耐腐蚀、强度高等特点,是反应堆耐事故燃料的候选材料之一。为分析碳化硅复合材料包壳燃料棒在失水事故下的综合性能,利用公开文献实验数据,拟合碳化硅复合材料物... 碳化硅复合材料具有热膨胀系数低、中子吸收截面低、抵抗热冲击、高温下耐腐蚀、强度高等特点,是反应堆耐事故燃料的候选材料之一。为分析碳化硅复合材料包壳燃料棒在失水事故下的综合性能,利用公开文献实验数据,拟合碳化硅复合材料物性公式,用FRAPTRAN对比分析与Zr4包壳燃料棒在同种工况下的性能差异。本文整理的公式和使用的方法可初步用于分析碳化硅复合材料燃料棒的综合性能。计算结果表明:在失水事故中,碳化硅复合材料的燃料棒失效时间长,平均温度低,可有效延缓事故进程。 展开更多
关键词 燃料棒 碳化硅复合材料 包壳 失水事故
Investigation of the interaction of material of fuel cladding for WWER-1000 reactor with steam at a temperature of accident overheatings 预览
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作者 Nadezhda Ishchenko Ivan Petelguzov Olena Slabospitska 《材料工程研究(英文)》 2019年第2期32-39,共8页
The subject of this study is the oxidation of fuel rod cladding made of material Zr1Nb(0.1% O) in steam at temperatures in the range of 660℃ to 1200℃ with a surface in the initial state (after manufacturing - grindi... The subject of this study is the oxidation of fuel rod cladding made of material Zr1Nb(0.1% O) in steam at temperatures in the range of 660℃ to 1200℃ with a surface in the initial state (after manufacturing - grinding) and after additional chemical etching. The changes in the microstructure of tubes due to the interaction with steam were investigated. A comparison was made between the oxidation rate of this material (weight gain) and the data on the oxidation of other alloys for nuclear power plants. The oxidation rate of Zr1Nb(0.1% O) is close to the oxidation rate of other zirconium alloys. It is shown that after chemical treatment of the surface of the samples there is a more even growth of oxide films, and they have a smaller thickness for the same time of exposure than after mechanical grinding. Surface treatment before oxidation also affects the change of microstructure of samples when heated to high temperatures. 展开更多
关键词 high-temperature oxidation nuclear power plants ZIRCONIUM tubes fuel rod CLADDING STEAM surface treatment alloy and oxide structure ACCIDENT OVERHEATING
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Epitaxial growth and oxidation behavior of an overlay coating on a Ni-base single-crystal superalloy by laser cladding
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作者 Jingjing Liang Yongsheng Liu +2 位作者 Jinguo Li Yizhou Zhou Xiaofeng Sun 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第2期344-350,共7页
An overlay coating material was deposited on a single crystal superalloy SRR99 by laser cladding.The microstructure and oxidation behavior of this coating was investigated through scanning electron microscopy(SEM) and... An overlay coating material was deposited on a single crystal superalloy SRR99 by laser cladding.The microstructure and oxidation behavior of this coating was investigated through scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results indicated that although the composition of the coating was chosen based on the γ’ composition in René N5 superalloy, the primary solidification phase of this coating during laser cladding was γ-Ni. Furthermore, under the laser cladding condition, fine parallel dendrites grew epitaxially in the coating from the substrate, indicating the single crystal structure of the substrate was reproduced. When the single crystal MCrAlY coating was oxidized at 1000?, both Al2O3 and Al2O3 formed during initial oxidation process. As the oxidation time proceeded, the presence of Al2O3 facilitated the formation of NiAl2O4 spinel oxide. Once the spinel was observed, it flourished and induced some porosity in the scale. When the scale thickness increased to 6–7 μm, large area spallation of the scale began. 展开更多
关键词 Laser CLADDING Single crystal growth EPITAXY OVERLAY COATING
Effect of scanning speeds on electrochemical corrosion resistance of laser cladding TC4 alloy
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作者 冯晓甜 雷剑波 +1 位作者 顾宏 周圣丰 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第2期383-390,共8页
In order to study the effect of scanning speed on the electrochemical corrosion resistance of laser cladding TC4 alloy in artificial seawater, the x-ray diffraction analysis, microstructure of cross-section, microhard... In order to study the effect of scanning speed on the electrochemical corrosion resistance of laser cladding TC4 alloy in artificial seawater, the x-ray diffraction analysis, microstructure of cross-section, microhardness variation, and impedance spectrum have been studied in comparison with the TC4 titanium alloy. The results show that the main phase of cladding coating is α-Ti, and the change of scanning speed has no obvious effect on it;therefore, the supersaturated α-Ti solid solution is formed, and the acicular α martensite is obtained. As the scanning speed increases, the microstructure of cladding coating is orthogonal basket-weave, the crystal surface spacing decreases, and the average microhardness of laser cladding TC4 alloy slightly increases. When the scanning speed increases to 10 mm/s, the microhardness is about 14.71%higher than that of the substrate, and the electrochemical corrosion resistance of laser cladding TC4 alloy is also improved,which is about 2.48 times more than the substrate. Grain refinement has a great effect on enhancing the anti-electrochemical corrosion. 展开更多
关键词 laser CLADDING TC4 alloy grain REFINEMENT ELECTROCHEMICAL corrosion
沥青包覆人造石墨炭化处理工艺 预览
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作者 冯国飞 武建国 +2 位作者 刘伟 徐生华 林治珠 《储能科学与技术》 CAS CSCD 2019年第3期580-582,共3页
为了提高人造石墨包覆后的炭化收率和电化学性能,本文采用改性沥青对人造石墨进行包覆,并经预氧化处理后再炭化。采用激光粒度分布仪、振实密度仪和比表面及孔径测试仪对炭化样品进行表征,并进一步对其电化学性能进行了研究。结果表明:... 为了提高人造石墨包覆后的炭化收率和电化学性能,本文采用改性沥青对人造石墨进行包覆,并经预氧化处理后再炭化。采用激光粒度分布仪、振实密度仪和比表面及孔径测试仪对炭化样品进行表征,并进一步对其电化学性能进行了研究。结果表明:炭化过程加入预氧化处理,有效地改善了结块现象,并极大的提高了负极材料的电化学性能。 展开更多
关键词 包覆 炭化 预氧化 锂离子电池 负极材料
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比粉与比能对激光熔覆NiWC25特性的影响 预览
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作者 李高松 李金华 +1 位作者 冯伟龙 单鹏超 《表面技术》 EI CAS CSCD 北大核心 2019年第5期253-258,共6页
目的探究激光熔覆过程中比粉和比能对合金粉末与基体的结合特性、熔覆层宏观形貌和微观结构、熔覆层最大宽度和结合宽度比值的影响规律,找出熔覆层既无柱节结构又具有良好冶金结合的比粉和比能的可选范围。方法采用正交实验和单一控制... 目的探究激光熔覆过程中比粉和比能对合金粉末与基体的结合特性、熔覆层宏观形貌和微观结构、熔覆层最大宽度和结合宽度比值的影响规律,找出熔覆层既无柱节结构又具有良好冶金结合的比粉和比能的可选范围。方法采用正交实验和单一控制变量相结合,制备出一组单道熔覆层,分析该熔覆层比粉和比能对柱节结构、临界结合结构、均匀圆柱结构的影响特性。结果当激光熔覆的比粉大于7vs/mm、比能大于200ws/mm时,熔覆层最大宽度与熔覆层结合宽度的比值大于1.41,熔覆层和基体之间出现间隙,使熔融合金粉末在熔覆过程中沿着垂直于基体方向塌陷,形成了明显柱节结构的熔覆层;当比能为200 ws/mm、比粉小于5vs/mm时,熔覆层的宏观形貌为均匀圆柱形结构,且熔覆层最大宽度与基体和NiWC25的结合宽度比值为1;当比粉大于7 vs/mm、比能小于100 ws/mm时,NiWC25和基体出现临界熔覆层,甚至出现基体和熔融Ni WC25合金粉末脱离现象。结论只要激光熔覆的比粉在3~5 vs/mm、比能在100~200 ws/mm范围内变动时,不仅能保证熔覆层无任何柱节结构,且基体和NiWC25结合宽度与熔覆层最大宽度比值恒等于1,从而使基体与NiWC25合金具有良好的冶金结合性能。 展开更多
关键词 比粉 比能 柱节 NiWC25 宽度比 熔覆
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管线内表面堆焊成形一体化装置的研制 预览
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作者 谢雨田 张体明 +2 位作者 陈玉华 胡锦扬 黄永德 《精密成形工程》 2019年第2期50-54,共5页
目的针对人工堆焊耐蚀耐磨合金层效率低、质量稳定性差等问题,研制一种管线内壁成形一体化成形装置。方法设计管线内壁堆焊制造焊接系统、枪体夹持系统、旋转系统、水平驱动系统和预热-后热处理系统,并将这些系统总装配合使用。结果实... 目的针对人工堆焊耐蚀耐磨合金层效率低、质量稳定性差等问题,研制一种管线内壁成形一体化成形装置。方法设计管线内壁堆焊制造焊接系统、枪体夹持系统、旋转系统、水平驱动系统和预热-后热处理系统,并将这些系统总装配合使用。结果实现了管线内壁堆焊制造的一体化成形。结论一次加工即可实现管线内壁预热、堆焊制造以及后热处理,极大提高了堆焊效率,同时能够保证堆焊层的成形质量。 展开更多
关键词 管线 内壁 堆焊 一体化成形
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Grain boundary and microstructure engineering of Inconel 690 cladding on stainless-steel 316L using electron-beam powder bed fusion additive manufacturing
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作者 I.A. Segura L.E. Murr +7 位作者 C.A. Terrazas D. Bermudez J. Mireles V.S.V. Injeti K. Li B. Yu R.D.K.Misra R.B. Wicker 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第2期351-367,共17页
This research explores the prospect of fabricating a face-centered cubic(fcc) Ni-base alloy cladding(Inconel 690) on an fcc Fe-base alloy(316 L stainless-steel) having improved mechanical properties and reduced sensit... This research explores the prospect of fabricating a face-centered cubic(fcc) Ni-base alloy cladding(Inconel 690) on an fcc Fe-base alloy(316 L stainless-steel) having improved mechanical properties and reduced sensitivity to corrosion through grain boundary and microstructure engineering concepts enabled by additive manufacturing(AM) utilizing electron-beam powder bed fusion(EPBF). The unique solidification and associated constitutional supercooling phenomena characteristic of EPBF promotes[100] textured and extended columnar grains having lower energy grain boundaries as opposed to random, high-angle grain boundaries, but no coherent {111} twin boundaries characteristic of conventional thermo-mechanically processed fcc metals and alloys, including Inconel 690 and 316 L stainless-steel.In addition to [100] textured grains, columnar grains were produced by EPBF fabrication of Inconel 690 claddings on 316 L stainless-steel substrates. Also, irregular 2–3 μm diameter, low energy subgrains were formed along with dislocation densities varying from 108 to 109 cm2, and a homogeneous distribution of Cr23C6 precipitates. Precipitates were formed within the grains(with 3 μm interparticle spacing),but not in the subgrain or columnar grain boundaries. These inclusive, hierarchical microstructures produced a tensile yield strength of 0.527 GPa, elongation of 21%, and Vickers microindentation hardness of 2.33 GPa for the Inconel 690 cladding in contrast to a tensile yield strength of 0.327 GPa, elongation of 53%, and Vickers microindentation hardness of 1.78 GPa, respectively for the wrought 316 L stainlesssteel substrate. Aging of both the Inconel 690 cladding and the 316 L stainless-steel substrate at 685?C for50 h precipitated Cr23C6 carbides in the Inconel 690 columnar grain boundaries, but not in the low-angle(and low energy) subgrain boundaries. In contrast, Cr23C6 carbides precipitated in the 316 L stainless-steel grain boundaries, but not in the low energy coherent {111} twin boundaries. Consequently, the Inconel6 展开更多
关键词 Additive manufacturing ELECTRON-BEAM powder bed FUSION (EPBF) INCONEL 690 CLADDING 316L stainless steel Grain boundary engineering Materials characterization Mechanical properties
Cladding of aluminum alloy 6061-T6 to mild steel by an electromagnetic tube bulging process: finite element modeling
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作者 Zhi-Song Fan Su-Ting Huang Jiang-Hua Deng 《先进制造进展:英文版》 CAS CSCD 2019年第1期73-83,共11页
Bimetal tubes have useful applications in various industries where service conditions demand more different requirements in the tube core than its outside surface. The recent use of electromagnetic forces to deform or... Bimetal tubes have useful applications in various industries where service conditions demand more different requirements in the tube core than its outside surface. The recent use of electromagnetic forces to deform or join metallic workpieces at high speeds has undergone rapid growth for materials processing. However, to date, no sufficient systematic understanding of the underlying principles of a subsequent high-speed electromagnetic tube bulging process to manufacture bimetal tubes has been gained. In this work, magnetic pulse cladding of Al/Fe clad bimetal tubes was analyzed by finite element modeling (FEM) using ANSYS software. The validity of FEM analyses was first confirmed by experiments in terms of the deformed shape. Second, the effect of cladding parameters (such as axial feeding being the dominant factor in the multi-step process) on the bulging and thinning behavior of the Al clad tube was presented in detail. Both the numerical simulation and experimental results show that no more than 70% of the bulging-coil length is an appropriate amount for the feeding length to prevent defects from being introduced by non-uniform deformation in the transition zone of the Al clad tube. The distributions of the magnetic flux line, magnetic force, and plastic strain in different cladding steps were then analyzed. It was concluded that during the multi-step cladding process, there was an uneven distribution of the magnetic field force along the transition zone. Consequently, inharmonious plastic deformation behavior occurs, which results in a limited acceleration of the transition zone to a certain impact velocity. 展开更多
关键词 BIMETAL tubes Magnetic pulse CLADDING Finite element (FE) simulation AXIAL FEEDING
Corrosion of New Zirconium Claddings in 500℃/10.3 MPa Steam:Effects of Alloying and Metallography
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作者 Jing-Jing Liao Zhong-Bo Yang +4 位作者 Shao-Yu Qiu Qian Peng Zheng-Cao Li Ming-Sheng Zhou Hong Liu 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第8期981-994,共14页
With the aim of improving corrosion resistance of rod cladding for in-service and accident conditions,six new zirconium alloys(named N1-N6)have been designed.The contents of Sn and Nb were optimized for better behavio... With the aim of improving corrosion resistance of rod cladding for in-service and accident conditions,six new zirconium alloys(named N1-N6)have been designed.The contents of Sn and Nb were optimized for better behavior at high-temperature pressurized water,and Fe,Cr,V,Cu or Mo elements were added to the alloys to adjust the corrosion behavioi\The current work focused on the rapid corrosion behavior in 500℃/10.3 MPa steam for up to 1960 h,aiming to test the corrosion resistance at high temperature.The structure of matrix and properties of second-phase particles(SPPs)were characterized to find the main differences among these alloys.All the six alloys exhibited better corrosion resistance than N36,and NI was shown to have the best performance.A careful analysis of the corrosion kinetics curves revealed that Cr was beneficial for severe condition.Elements Fe,Cr,V,Cu or Mo aggregated into SPPs with diiferent concentrations and structures.This was demonstrated to be the main reason for different corrosion resistance.Due to good processing control,all alloys had a uniform structure and a uniform distribution of SPPs.As for N4,N6 and N36,the existing of large-size SPPs(450 nm)might be a contributing factor of the relatively poor corrosion resistance. 展开更多
关键词 NEW ZIRCONIUM cladding CORROSION behavior ALLOYING elements METALLOGRAPHY Second-phase particles
Neutronic analysis of silicon carbide cladding accident-tolerant fuel assemblies in pressurized water reactors 预览
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作者 Zhi-Xiong Tan Jie-Jin Cai 《核技术:英文版》 SCIE CAS CSCD 2019年第3期105-113,共9页
In resonance with the Fukushima Daiichi Nuclear Power Plant accident lesson, a novel fuel design to enhance safety regarding severe accident scenarios has become increasingly appreciated in the nuclear power industry.... In resonance with the Fukushima Daiichi Nuclear Power Plant accident lesson, a novel fuel design to enhance safety regarding severe accident scenarios has become increasingly appreciated in the nuclear power industry. This research focuses on analysis of the neutronic properties of a silicon carbide (SiC) cladding fuel assembly, which provides a greater safety margin as a type of accident-tolerant fuel for pressurized water reactors. The general physical performance of SiC cladding is explored to ascertain its neutronic performance. The neutron spectrum, accumulation of 239Pu, physical characteristics, temperature reactivity coefficient, and power distribution are analyzed. Furthermore, the influences of a burnable poison rod and enrichment are explored. SiC cladding assemblies show a softer neutron spectrum and flatter power distribution than conventional Zr alloy cladding fuel assemblies. Lower enrichment fuel is required when SiC cladding is adopted. However, the positive reactivity coefficient associated with the SiC material remains to be offset. The results reveal that SiC cladding assemblies show broad agreement with the neutronic performance of conventional Zr alloy cladding fuel. In the meantime, its unique physical characteristics can lead to improved safety and economy. 展开更多
关键词 Accident-tolerant fuels Silicon CARBIDE CLADDING NEUTRONIC characteristics Pressurized water REACTOR
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Highly Sensitive Refractive Index Sensor Based on Polymer Long-Period Waveguide Grating With Liquid Cladding
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作者 Lingfang WANG Keyu REN +1 位作者 Bao SUN Kaixin CHEN 《光子传感器:英文版》 EI CAS CSCD 2019年第1期19-24,共6页
We propose a novel structure and unique sensing mechanism bio-chemical sensor which is fabricated by a polymer long-period waveguide grating with the detection liquid directly as the waveguide cladding.Quantitative de... We propose a novel structure and unique sensing mechanism bio-chemical sensor which is fabricated by a polymer long-period waveguide grating with the detection liquid directly as the waveguide cladding.Quantitative detection is realized from analyzing the output absorption spectrum and resonant wavelength shift related to the liquid detection concentration.The proposed polymer long-period waveguide grating based liquid refractive-index sensor is developed experimentally,the high sensitivity of 1.01×10^4nm/RIU is achieved,and the temperature stability coefficient is 1.47nm/℃.Theoretically and experimentally,this work has been demonstrated to have potential application in chemical and biological detections and may provide an important technical support for solving today's increasingly serious civil problems such as food safety and drug safety, which will also have the important scientific significance and application prospects. 展开更多
关键词 Optical SENSOR POLYMER WAVEGUIDES long-period WAVEGUIDE GRATINGS liquid CLADDING
海洋环境中活塞杆两种喷涂防腐技术测试报告分析和工程应用初探 预览 被引量:1
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作者 刘旭辉 陈小明 +2 位作者 黄海杨 伏利 石磊 《水利与建筑工程学报》 2019年第1期108-112,118共6页
活塞杆是液压启闭机的关键部件,其在海洋环境下的防腐蚀寿命直接决定整套液压启闭机的使用寿命。通过对海洋环境金属腐蚀规律、活塞杆防腐技术现状等进行了归纳研究,对活塞杆陶瓷喷涂和喷涂镍铬合金测试报告进行了对比分析,提出了海洋... 活塞杆是液压启闭机的关键部件,其在海洋环境下的防腐蚀寿命直接决定整套液压启闭机的使用寿命。通过对海洋环境金属腐蚀规律、活塞杆防腐技术现状等进行了归纳研究,对活塞杆陶瓷喷涂和喷涂镍铬合金测试报告进行了对比分析,提出了海洋环境活塞杆防腐技术发展的建议,以共同推动水工金属结构海洋环境防腐技术的发展。 展开更多
关键词 海洋环境 液压启闭机活塞杆 腐蚀 熔覆 测试分析 技术
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TIG熔覆原位自生TiC-TiB2/Fe复合涂层 预览
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作者 马宁 赵迪 +2 位作者 张柯柯 杨跃 尹丹青 《焊接学报》 CSCD 北大核心 2018年第10期124-128,134共6页
利用氩弧作为热源,以G302铁基合金粉、FeTi70粉和B4C粉作为原料粉末,在Q235表面原位生成TiCTiB2增强的铁基复合涂层.采用一系列的分析测试方法对涂层进行了表征,结果表明,氩弧熔覆过程冶金反应充分,熔覆层中生成了TiC,TiB2和M7C3等硬质... 利用氩弧作为热源,以G302铁基合金粉、FeTi70粉和B4C粉作为原料粉末,在Q235表面原位生成TiCTiB2增强的铁基复合涂层.采用一系列的分析测试方法对涂层进行了表征,结果表明,氩弧熔覆过程冶金反应充分,熔覆层中生成了TiC,TiB2和M7C3等硬质增强相;熔覆层组织呈现出由母材界面到熔覆层表面硬质相逐渐增多的梯度分布特征.增加FeTi70和B4C粉末比例提高了熔覆层硬度,质量比为G302:FeTi70:B4C=6:3:1时,试样最大硬度达到976 HV0.1,是母材硬度的5倍左右.在与GCr15钢对磨时,熔覆试样磨损量仅为Q235钢的1/30左右,熔覆层磨损表面基本无塑性变形痕迹,涂层中坚硬的TiC,TiB2陶瓷相起到阻磨作用. 展开更多
关键词 熔覆 碳化钛 耐磨 复合涂层
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FM-52M镍基合金堆焊层高温拉伸性能研究
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作者 方虎 李东 +2 位作者 曾春杰 邵世友 张涛 《热加工工艺》 CSCD 北大核心 2018年第17期59-62,共4页
在304不锈钢钢板采用TIG堆焊了FM-52M镍基合金,并利用Gleeble热模拟试验机对FM-52M堆焊层试样在不同条件下的高温拉伸性能进行了研究。结果表明:经750℃保温30 min处理后,FM-52M合金的强度与750℃保温30 s处理的相比明显降低;在高温、... 在304不锈钢钢板采用TIG堆焊了FM-52M镍基合金,并利用Gleeble热模拟试验机对FM-52M堆焊层试样在不同条件下的高温拉伸性能进行了研究。结果表明:经750℃保温30 min处理后,FM-52M合金的强度与750℃保温30 s处理的相比明显降低;在高温、应力缓慢加载的条件下,FM-52M的力学性能明显下降。热处理温度为950℃时,拉伸速率为0.01 mm/s的堆焊试样强度和断后伸长率均比拉伸速率为0.5 mm/s的小。经过1200℃的峰值温度保温后,合金的屈服强度比950℃的试样略低,但断后伸长率更好。 展开更多
关键词 FM-52M 堆焊层 热处理 拉伸速率 峰值温度
一种热煨弯管包覆式3LPE防腐新工艺 预览
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作者 范静 陈惠珍 杨锟昊 《全面腐蚀控制》 2018年第7期27-29,共3页
热煨弯管包覆式3LPE防腐工艺与冷带热熔3LPE防腐工艺相比较具有均衡防腐层厚度,极大节约了原材料的优点,与多层粉末喷涂3LPE工艺相较具有防腐层厚度不受工艺限制、防腐层强度、韧性等机械性能好等优点而备受关注,但是热煨弯管包覆式3LP... 热煨弯管包覆式3LPE防腐工艺与冷带热熔3LPE防腐工艺相比较具有均衡防腐层厚度,极大节约了原材料的优点,与多层粉末喷涂3LPE工艺相较具有防腐层厚度不受工艺限制、防腐层强度、韧性等机械性能好等优点而备受关注,但是热煨弯管包覆式3LPE防腐工艺在大面积推广前还需要解决好高精度的自动控制系统,更加优化的复合式包覆模具设计等问题。 展开更多
关键词 热煨弯管 包覆式 3LPE防腐
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Microstructure and properties of in-situ chromium carbide composite coating by laser cladding 预览
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作者 何亚楠 宋强 +2 位作者 孙康 赵玉桥 崔洪芝 《中国焊接:英文版》 EI CAS 2018年第4期10-17,共8页
Using Ni/Cr/graphite powder blends as raw powders,a Ni matrix composite coating reinforced by in-situ carbide,was fabricated on the surface of Q235 by means of laser cladding. These microstructure and properties were ... Using Ni/Cr/graphite powder blends as raw powders,a Ni matrix composite coating reinforced by in-situ carbide,was fabricated on the surface of Q235 by means of laser cladding. These microstructure and properties were discussed. The result of phase analysis( XRD) and microstructure investigation( SEM) showed that the coatings consist mainly of Cr3 C2,Cr7 C3 and γ-( Ni,Cr),which are consistent with the thermodynamic calculations. The wear morphology of the coatings was also examined. The results of dry sliding wear tests of different Cr/C ratio show that the wear resistances of the Cr3 C2-reinforced coating,respectively,are 13. 4,9. 5,9. 1 and 6. 5 times higher than that of the substrate and the main wear mechanisms of the coatings are adhesion and abrasive wear with slight oxidation. 展开更多
关键词 laser CLADDING IN-SITU synthesized chromium CARBIDE wear resistance worn mechanism
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壳核结构复合粉末的制备及其在热喷涂领域的应用
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作者 史娜 冯潇 +1 位作者 何力 邢亚哲 《热加工工艺》 CSCD 北大核心 2018年第24期1-5,共5页
壳核结构复合粉末兼有壳、核两种材料的优良性能,被广泛应用于电力、催化及热喷涂等领域。介绍了壳核结构复合粉末的包覆机理和典型的制备方法,综述了壳核结构复合粉末在热喷涂领域中的应用,最后指出了壳核结构复合粉末今后的研究方向。
关键词 壳核结构 包覆 制备 热喷涂 应用
镍基合金堆焊层在除氧和含氢高温水中氧化膜的性能 预览
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作者 贾一波 凌思纯 +6 位作者 吕战鹏 马佳荣 熊琪 李红娟 陈俊劼 李双燕 张茂龙 《腐蚀与防护》 北大核心 2018年第7期530-534,共5页
研究了镍基合金堆焊层在模拟压水堆一回路水中生成的表面氧化膜的特性,对比了镍基合金在除氧水(溶解氧含量〈5μg/L)和含氢水(溶解氢含量约为2.6 mg/L)中生成的氧化膜的异同。结果表明:在325℃下浸泡146h后,除氧水中镍基合金表面... 研究了镍基合金堆焊层在模拟压水堆一回路水中生成的表面氧化膜的特性,对比了镍基合金在除氧水(溶解氧含量〈5μg/L)和含氢水(溶解氢含量约为2.6 mg/L)中生成的氧化膜的异同。结果表明:在325℃下浸泡146h后,除氧水中镍基合金表面生成了稀疏分布的氧化物颗粒,含氢水中镍基合金表面则几乎无氧化物颗粒,只生成了一层黑色的氧化膜。含氢水中,在堆焊层厚度方向上越靠近堆焊层-基体熔合线,镍基合金表面生成的氧化物颗粒也越密集,其氧含量也越高,这表明堆焊层过渡区材料特性与高温水中氧化膜具有相关性。 展开更多
关键词 压水堆核电站 堆焊层 镍基合金 高温水 氧化膜
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Optimization of laser cladding process for additive repair of high temperature and high pressure valve sealing surface 预览
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作者 Lei Che Wenlei Sun +1 位作者 Guan Zhang Jiaxin Han 《材料科学:材料评论》 2018年第2期34-49,共16页
Laser cladding technology is highly suitable for the remanufacturing of thin-walled and easily deformable parts due to its concentrated energy density. Due to the high temperature and high pressure corrosion environme... Laser cladding technology is highly suitable for the remanufacturing of thin-walled and easily deformable parts due to its concentrated energy density. Due to the high temperature and high pressure corrosion environment, the valve sealing surface is prone to corrosion, wear and other failures. A nickel-based tungsten carbide alloy layer was prepared on the valve sealing surface substrate material by laser cladding process. By designing orthogonal experiments, the effects of laser power (P), scanning speed (Vb), powder feeding rate (Vf), and WC content (wt%) on the alloy layer were investigated. A fuzzy comprehensive evaluation method including macroscopic quality, microstructure, microhardness, anti-wear performance, oxidation resistance, compactness and corrosion resistance was proposed. The experimental results showed that the hardness, oxidation resistance and corrosion resistance of the laser alloy layer are significantly improved compared with the matrix;the optimum process parameters and the addition ratio of WC powder are laser power (P) of 1.1 kW and scanning speed (Vb) of 800 mm/min. The powder feeding rate (Vf) was 20%, and the WC content was 20% by weight. 展开更多
关键词 laser CLADDING HIGH temperature and HIGH pressure process OPTIMIZATION VALVE SEALING surface fuzzy comprehensive evaluation
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