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Journal of Iron and Steel Research International 2012年第5期19卷 63-68页

作者： hu zheng-fei WANG Chun-xu School of Material Science and Engineering Tongji UniversityShanghai 200092China China Iron and Steel Institute Group Beijing 100081China

The effects of spinning deformation and subsequent heat treatments on the mechanical properties and microstructure of 18Ni Co-free Maraging steel （T250） tube were evaluated comparatively with the perform. An obvious radial shrinkage is detected in spun tubes after heat treatment and the magnitude of the shrinkage induced by solution treatment is almost the same as that by aging. Plastic deformation during spinning elongated the grains severely in the direction of metal flow. The solution treatment resulted in a drastically refined grain and recrystallised microstructure, removing the effect of plastic deformation, relieving the tangential residual stress and strain and improving hardness. Subsequent aging obtained a tempered microstructure, enhancing hardness values strikingly for precipitation strengthening. XRD （X-ray diffraction） analysis indicated that the reversed austenite formed in a plate-like along the grain boundaries and the volume fraction of austenite in spun tube was more than double that in the preform. These results imply that the residual stress and stain induced by spinning process and reversed austenite forming during aging might have the similar contribution to the radical shrinkage.

关键词： maraging steel spinning process plastic deformation heat-treatment microstructure reversed austenite

Microstructure Evolution in 9Cr Martensitic Steel During Long-Term Creep at 650℃

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Journal of Iron and Steel Research International 2012年第7期19卷 55-59页

作者： hu zheng-fei WANG Qi-jiang ZHANG Bin School of Material Science and Engineering Tongji University Shanghai 200092 China Institute of Baosteel Shanghai 201900 China

Standardarized creep and rupture strength tests were conducted for commercial T91 martensitic heat-resistant steel at 650℃and corresponding microstructure was characterized by BSED, TEM and EDS. The martensitic microstructure degenerated seriously during creep exposure, including martensitic substructure recovering, carbides coarsening, dissolving and precipitating. EDS analysis shows that the M23C6 carbides in different morphologies have dissimilar compositions. The rod/sheet like M23 C6 particles within the matrix contain more additions, which might precipitate in situ while fine MX particles were re-solving. The high content of silicon in these rod/sheet like M2aC6 carbides is probably related to self diffusion coefficient increasing for the exposed condition at 650 ~C close to Curie temperature To. For those reasons, martensite substructure becomes unstable, and microstructure evolution is accelerated and leads to creep strength deteriorating severely.

关键词： T91 steel creep strength microstructure carbide coarsening self-diffusion

M2C Precipitate in Isothermal Tempering of High Co-Ni Alloy Steel

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Journal of Iron and Steel Research International 2001年第2期8卷 56-58页

作者： hu zheng-fei WU Xing-fang LI Xiu-qiu WANG Chun-xu FANG Xin University of Science and Technology Beijing Central Iron & Steel Research Institute Fushun Special Steel Co

It is possible to measure different position along the axle direction of tappet. According to the maximum output of signal, the boundary of white iron structure and mottled iron structure can be deduced, and at the same time, it is possible to use inductance displacement meter to show the chill depth which is the distance from the boundary to the end.

关键词： magnetic permeability chilled cast iron chill depth

Microstructure and Hardness of T250 Maraging Steel in Heat Affected Zone

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Journal of Iron and Steel Research International 2009年第1期16卷 87-91页

作者： MO De-feng hu zheng-fei CHEN Shu-juan WANG Chun-xu HE Guo-qiu School of Material Science and Engineering Tongji University Shanghai 200092 China Central Iron and Steel Research Institute Beijing 100081 China

Electron-beam （EB） welding was used in T250 maraging steel, microstructures of both base material and heat affected zone （HAZ） were investigated by optical microscopy （OM）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）, and microhardness was tested. The results showed that during EB welding, the HAZ of T250 maraging steel exhibited a continuous gradient structure. The microstrueture of the entire HAZ, from fusion line, could be divided into four zones： fusion zone, overheated zone, transition zone, and hardened zone. The microhardness showed a distinct regularity in each area. The softest region was the fusion zone, whereas the hardest was the hardened zone. In the overheated zone, the hardness increased as the grain size decreased. Furthermore, in the transition zone, the hardness level dropped noticeably. The peak temperature during the thermal cycle had a great influence on the formation of reverted austenite and dissolution of the precipitated particles, which contributed a lot to the microstructure and hardness of this material.

关键词： T250 maraging steel electron-beam weld microstructure microhardness

Failure Analysis of Electron Beam Weld Joints for 18Ni Co-free Maraging Steels

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金属热处理 2007年第Z1期32卷 384-389页

作者：莫德锋同济大学

Microstructure of two different 18Ni Co-free maraging specimens and their electron beam weld joints were investigated comparatively by optical microscopy and SEM. It is showing that both of the steels are typical lath martensite, however, one grain size is about three times as another one, and XRD reveals that the amount of the retained austenitic phase in the former is less then the latter. The austenite distributes in plate form along granular and lath boundaries while some in fine particle within the matrix. The microstructural difference between two specimens led to diverse behaviors in electron beam welding. The first specimen is weldable well but the second shows obvious welding defects of pits and burn-through holes in weld face. The welding microstructure exhibits a typical dendritic morphology, and the grains in the heat-affected zone recrystallized and grew up obviously for high temperature heated by welding electron beam. The weldablity is relative to the thermal conduction performance of the base materials,which is contributed greatly for grain size and austenite content.

关键词： maraging steel electron beam welding failure Analysis microstructure

温度对P92耐热钢高温水中应力腐蚀开裂行为的影响

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材料热处理学报 2015年第8期36卷 121-125页

作者：张振胡正飞同济大学材料科学与工程学院上海201804

在高温水环境中采用线性伏安法和慢拉伸试验法,分别研究了温度对国产P92钢点蚀形核及应力腐蚀开裂的影响规律。线性伏安法结果表明:随着温度的提高,P92钢在水中的耐腐蚀性能逐渐降低,晶界处点蚀形核数增多;慢拉伸试验结果表明,P92钢在... 详细信息

在高温水环境中采用线性伏安法和慢拉伸试验法,分别研究了温度对国产P92钢点蚀形核及应力腐蚀开裂的影响规律。线性伏安法结果表明:随着温度的提高,P92钢在水中的耐腐蚀性能逐渐降低,晶界处点蚀形核数增多;慢拉伸试验结果表明,P92钢在试验条件下具有应力腐蚀开裂敏感性和动态应变时效(DSA)倾向,且随温度升高增强。通过扫描电镜(SEM)对试样断口截面及侧面形貌进行分析,结果表明随着温度的升高,断口侧面应力腐蚀裂纹以沿晶形式向内扩展,断口边缘呈明显脆性断裂特征。

关键词： P92钢高温水温度应力腐蚀开裂

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9Cr马氏体耐热钢发展及其蠕变寿命预测

钢铁研究学报 2010年第1期22卷 26-31页

作者：张斌胡正飞同济大学材料科学与工程学院上海市金属功能材料开发应用重点实验室上海200092

9Cr马氏体耐热钢是目前热电厂关键设备制造的主选钢种,其最大的特点是600℃左右高温服役条件下良好的持久强度,较好的抗腐蚀性能。本文主要阐述了9Cr马氏体耐热钢的发展及其研究的最新进展,从材料的组织结构、蠕变特性和蠕变寿命预测等... 详细信息

9Cr马氏体耐热钢是目前热电厂关键设备制造的主选钢种,其最大的特点是600℃左右高温服役条件下良好的持久强度,较好的抗腐蚀性能。本文主要阐述了9Cr马氏体耐热钢的发展及其研究的最新进展,从材料的组织结构、蠕变特性和蠕变寿命预测等多方面叙述了有关9Cr马氏体耐热钢的研究动态。

关键词： 9Cr马氏体耐热钢组织结构蠕变强度失效寿命预测

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan Ren fei zheng Tingwei Cao Qiang Wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina College of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2)forcing Key parameter Parameter estimation Data assimilation Machine learning

圆锥扫描自动跟踪体制在船载“动中通”中的应用

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南京邮电大学学报（自然科学版） 2006年第3期26卷 92-94页

作者：季鸿宇胡正飞南京邮电大学通信与信息工程学院江苏南京210003 南京邮电大学数理学院江苏南京210003

结合实际研究项目介绍了一种新型船载卫星通信系统的关键技术,该系统采用的是捷联式的有源稳定跟踪平台,特点在于利用圆锥扫描原理实现天线姿态稳定跟踪,从而降低了系统对天线稳定平台的精度要求,主要探讨了圆锥扫描技术在天线自动跟踪... 详细信息

结合实际研究项目介绍了一种新型船载卫星通信系统的关键技术,该系统采用的是捷联式的有源稳定跟踪平台,特点在于利用圆锥扫描原理实现天线姿态稳定跟踪,从而降低了系统对天线稳定平台的精度要求,主要探讨了圆锥扫描技术在天线自动跟踪系统中的应用。阐述了圆锥扫描自动跟踪的原理、系统组成以及系统的具体实现方案,分析了扫描参数对系统性能的影响及选择原则。实验测试表明,该系统能够获得较高的跟踪精度和跟踪实时性,能够使天线稳定地对准卫星。

关键词：圆锥扫描天线自动跟踪波束偏角扫描频率

热处理对新型13Cr4Ni低温耐腐蚀不锈钢性能的影响

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金属热处理 2008年第7期33卷 57-61页

作者：胡正飞张建权同济大学材料科学与工程学院上海200092 美国钻采系统中国有限公司上海200437

制备了一种新型13Cr4Ni马氏体不锈钢并研究了热处理对其硬度和耐腐蚀性的影响。不同的热处理工艺试验比较显示,材料达到低硬度和高耐腐蚀性要求的最佳热处理工艺为780℃×6h退火+1040℃×1h空冷淬火+675℃×7h一次回火+605℃×5h二次回... 详细信息

制备了一种新型13Cr4Ni马氏体不锈钢并研究了热处理对其硬度和耐腐蚀性的影响。不同的热处理工艺试验比较显示,材料达到低硬度和高耐腐蚀性要求的最佳热处理工艺为780℃×6h退火+1040℃×1h空冷淬火+675℃×7h一次回火+605℃×5h二次回火处理。微观结构分析表明,热处理后试验钢的组织为典型的回火马氏体,马氏体晶内有细小弥散的碳化物析出,逆转变奥氏体以膜状形态分布于晶界。在2%NaCl溶液中Tafel极化曲线测试结果显示,试验钢的耐腐蚀性明显优于410不锈钢。

关键词： 13Cr4Ni不锈钢热处理硬度低温耐腐蚀性能