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高应变率加载结合退火处理下CoCrNi中熵合金的微观组织演化与力学行为研究

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高应变率加载结合退火处理下CoCrNi中熵合金的微观组织演化与力学...

作者：秦浩淋成都大学

学位级别：硕士

多主元合金,包括高熵合金和中熵合金,作为一类新型的结构材料,具有独特的显微组织和有优异的机械、物理和化学特性等,在交通、航空、航天等领域具有可期的应用潜力,吸引了越来越多研究者的注意。其中具有fcc结构的中高熵合金通常拥有优... 详细信息

多主元合金,包括高熵合金和中熵合金,作为一类新型的结构材料,具有独特的显微组织和有优异的机械、物理和化学特性等,在交通、航空、航天等领域具有可期的应用潜力,吸引了越来越多研究者的注意。其中具有fcc结构的中高熵合金通常拥有优异的塑性和适中的强度,受到了广泛关注。近年来,在众多fcc结构的中高熵合金中,CoCrNi合金在室温和低温下都呈现出良好的强度和韧性匹配,同时CoCrNi合金具有较低的层错能和孪晶应力,更容易实现在较宽的应变范围内生成更多的纳米孪晶,因此得到了大量关注。但是,关于CoCrNi合金在高应变率下的微观组织演化和微观力学行为的规律尚未清晰,缺乏系统研究亟待解决。基于此,本文围绕CoCrNi合金,进行了动态冲击实验,并以此为研究对象,同时结合退火处理,采用力学试验测试、微观形貌分析、有限元模拟计算与理论公式拟合推导相结合的方法,系统的研究了CoCrNi中熵合金的力学响应、力学性能、微观结构和变形机理。首先采用真空电弧熔炼法制备了CoCrNi中熵合金,然后将CoCrNi中熵合金进行热轧使其厚度降低50%得到初始态CoCrNi中熵合金,再利用一级轻气炮加载手段制备了一种产生严重塑性变形的CoCrNi中熵合金,为研究动态冲击过程中应力应变的变化采用了有限元模拟再现了冲击过程。同时通过控制加载手段,受到冲击加载的CoCrNi中熵合金的微观组织中产生了梯度结构,这也为制备梯度中高熵合金材料提供了新的思路。研究发现经过动态冲击加载的初始态CoCrNi中熵合金的屈服强度由510MPa显著提升到1180MPa,但是塑性损失十分严重,均匀伸长率由32.5%下降至0.5%。为谋求一个强-塑性相对平衡的状态,对动态冲击后的CoCrNi中熵合金进行了不同温度的退火处理,最后发现在650℃退火30min条件下合金强度达到屈服强度734MPa、均匀伸长率22.9%的强-塑性相对平衡状态。

关键词：多主元合金 fcc 高应变率力学性能

催化裂化催化剂形态分析与监测技术的应用及优点

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石化技术 2024年第5期31卷 4-7页

作者：董峰邸军利胡光亮中国石油化工股份有限公司天津分公司天津300271

催化裂化催化剂形态分析与监测技术在石油化工催化裂化领域中的应用越来越广泛。本文应用了催化裂化催化剂形态分析与监测系统技术针对催化裂化催化剂生产中常见的问题,如反应中催化剂剂耗和产品收率等问题,介绍了催化剂显微诊断技术的... 详细信息

催化裂化催化剂形态分析与监测技术在石油化工催化裂化领域中的应用越来越广泛。本文应用了催化裂化催化剂形态分析与监测系统技术针对催化裂化催化剂生产中常见的问题,如反应中催化剂剂耗和产品收率等问题,介绍了催化剂显微诊断技术的基本原理和在解决催化剂各种问题中的应用。本文将为催化裂化反应的研究提供新思路和研究方向。

关键词：催化剂形态分析显微诊断 fcc 操作诊断

脱硝助燃剂在燕山石化2.0Mt/a催化裂化装置上的工业应用

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中外能源 2024年第2期29卷 69-73页

作者：安士新贾振东齐笑达杨大伟刘天齐谭卫东中国石油化工股份有限公司北京燕山分公司北京102500 山东骏飞环保科技有限公司山东淄博255400 中国石化集团资产经营管理有限公司齐鲁石化分公司山东淄博255434

燕山石化炼油厂2.0Mt/a三催化装置无外排烟气脱硝工艺环保设施,为了确保装置外排烟气中NO_(x)排放浓度满足生产工艺和小于100mg/m^(3)的当地环保要求,通过对装置再生单元进行研究分析,发现操作方通过降低高温烟道氧含量及维持贫氧燃烧... 详细信息

燕山石化炼油厂2.0Mt/a三催化装置无外排烟气脱硝工艺环保设施,为了确保装置外排烟气中NO_(x)排放浓度满足生产工艺和小于100mg/m^(3)的当地环保要求,通过对装置再生单元进行研究分析,发现操作方通过降低高温烟道氧含量及维持贫氧燃烧状态来控制NOx数值,出现外排烟气中CO和VOCs浓度均超过规定排放值的现状。为有效解决装置外排烟气中NO_(x)、VOCs及CO浓度不能同时达标的问题,结合装置贫氧再生工艺特点,选用加注LZ-5G贫氧型脱硝助燃剂进行工业试用。工业应用结果表明:装置再生系统加注LZ-5G贫氧型剂后,外排烟气中NO_(x)含量能够稳定在75mg/m^(3)以下,CO含量由体积浓度1%降低至0.05%以下,VOCs含量由40mg/m^(3)降至15mg/m^(3)以内,吨焦炭产汽量由7.5t增加至7.75t,同时烟气脱硫废水中的氨氮含量由10.12mg/L降低至2.04mg/L。LZ-5G贫氧型脱硝助燃剂可有效解决装置外排烟气中NO_(x)、VOCs及CO浓度超标问题,改善和提高了高温烟道燃烧效率,同时该剂的应用对催化裂化产品分布、性质及催化剂流化未产生负面影响。

关键词： fcc 贫氧再生脱硝助燃剂 NO_(x) CO VOCs

Nonlinear Bending of fcc Nanoplates Based on a Quasi-Continuum Model

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Acta Mechanica Solida Sinica 2022年第6期35卷 1030-1039页

作者： Wenjing Zhan Yaqi Guo Ying Zhao Guohua Nie School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

A quasi-continuum model of plate-type nanomaterials with the face-centered cubic crystal structures is proposed in this paper.The fundamental governing equations for the nonlinear bending of the nanoplates are given by using the principle of minimum potential energy.Specifically,the analytical solution is derived for cylindrical bending deformation of the structure under uniform transverse loading fixed at two sides based on the modified iterative method.A lattice finite element model is established to verify the present quasi-continuum model.Meanwhile,the corresponding solution by adopting the classical continuous plate theory is presented,in which two cases are considered for use of bulk values(limit values)and nanovalues of both elastic modulus and Poisson's ratio.The difference among the quasi-continuum and continuous models are discussed by computation.

关键词： fcc Nanoplates Quasi-continuum model Size effect Nonlinear bending

fcc coprocessing oil sands heavy gas oil and canola oil. 3. Some cracking characteristics

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Green Energy & Environment 2019年第1期4卷 83-91页

作者： Siauw H.Ng Nicole E.Heshka Ying Zheng Qiang Wei Fuchen Ding Natural Resources Canada CanmetENERGY Department of Chemical Engineering University of New Brunswick State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing Institute of Petrochemical Technology

Coprocessing of bitumen-derived feeds and biomass through a fluid catalytic cracking(fcc) route has the potential to assist in the reduction of fuel and petroleum product carbon footprints while meeting government regulatory requirements on renewable transportation fuels. This approach is desirable because green house gas(GHG) emissions for producing renewable biofuels are significantly lower than those for fossil fuels, and coprocessing can be executed using existing refining infrastructure to save capital cost. The present study investigates the specific fcc performances of pure heavy gas oil(HGO) derived from oil sands synthetic crude, and a mixture of 15 v% canola oil in HGO using a commercial equilibrium catalyst under typical fcc conditions. Cracking experiments were performed using a bench-scale Advanced Cracking Evaluation(ACE) unit at fixed weight hourly space velocity(WHSV) of 8 h^(-1), 490–530℃, and catalyst/oil ratios of 4–12 g/g. This work focuses on some cracking phenomena resulting from the presence of oxygen in the blendda lower heat requirement for cracking due to the exothermic water formation, which also entails lower hydrogen yield at a given severity. The distribution of feed oxygen in gaseous and liquid products, the mitigation in GHG emissions, and the technological and economical advantages of the coprocessing option are also discussed.

关键词： fcc coprocessing Microactivity test(MAT) unit Four-lump kinetic model Heat of formation of water vapour Carbon footprint reduction

Determination of Sulfides in fcc Gasoline by Using the Potentiometric Titration of Lead Tetraacetate

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Chinese Journal of Chemical Engineering 2004年第3期12卷 448-450页

作者：罗立文夏道宏 College of Chemistry and Chemical Engineering State Key Laboratory of Heavy Oil Processing University of Petroleum(East China) Dongying 257061 China College of Chemistry and Chemical Engineering State Key Laboratory of Heavy Oil Processing University of Petroleum(East China) Dongying 257061 Chinaompared with conventional method of violet spectrum determination of the content of sulfides in fluid catalytic cracking (FCC) gasoline by using the potentiometric titration of lead tetraacetate has some advantages such as clear potentiometric abrupt change at the stoichiometric point stable potentiometric value exact and credible results and simple operation. The content of sulfides in FCC gasoline of Shenghua refinery is 0.136% by this method. The standard deviation about this method is less than 0.01% and the relative standard deviation is less than 2.42%.

Compared with conventional method of violet spectrum, determination of the content of sulfides in fluid catalytic cracking (fcc) gasoline by using the potentiometric titration of lead tetraacetate has some advantages such as clear potentiometric abrupt change at the stoichiometric point, stable potentiometric value, exact and credible results, and simple operation. The content of sulfides in fcc gasoline of Shenghua refinery is 0.136% by this method. The standard deviation about this method is less than 0.01% and the relative standard deviation is less than 2.42%.

关键词： fcc 硫化物汽油电势滴定法检测技术催化裂化工艺

Analysis of fcc sheet metal forming with rate-independent polycrystalline plasticity FEM

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中国有色金属学会会刊：英文版 2004年第2期14卷 362-365页

作者：张少睿李大永罗应兵彭颖红 School of Mechanical Engineering

A rate-independent polycrystalline plasticity constitutive model considering self and latent hardening was developed. Next, a new orientation probability assignment method was proposed and the crystal orientations were assigned to FE integration points, which represent crystals and can rotate individually. Then cup drawing of fcc aluminum sheet was studied using crystalline plasticity finite element analysis. The results show that the validity of proposed model is proved through comparison between numerical results and experimental ones. {001} texture can lead to earing at 45° direction, while {124} texture at 0° and 90° directions. For the rolled aluminum sheet, which contains strong {001} texture, earing is formed at 45° direction after cup drawing. For the annealing aluminum sheet, due to the balance between two main textures, the flange earing tendency is not obvious.

关键词：面心立方结构金属材料多晶体 FEM fcc 有限元数值模拟塑性变形

The intrinsic mechanism of corrosion resistance for fcc high entropy alloys

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Science China(Technological Sciences) 2018年第2期61卷 189-196页

作者： shang xuliang wang zhijun he feng wang jincheng li junjie yu jiakang state key laboratory of solidification processing northwestern polytechnical universityXi’an 710072China

The concept of high entropy alloys(HEAs) or multi-principal component alloys has inspired a great progress of physical metallurgy along with several unusual phenomena. The high corrosion resistance of HEAs was frequently mentioned but without convincing explanations. In this paper, the intrinsic mechanism of corrosion resistance in fcc HEAs was revealed by designing equal atomic alloys with single solid solution phase. The results showed that the Cr element in fcc HEAs played the dominant role in the corrosion resistance rather than the simple structure from high entropy effect or uniform element distribution.

关键词： fcc 腐蚀合金机制熵物理冶金学 HEA 说服力

Porcine FcεRI Mediates Porcine Reproductive and Respiratory Syndrome Virus Multiplication and Regulates the Inflammatory Reaction

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Virologica Sinica 2018年第3期33卷 249-260页

作者： Peidian Shi Lilin Zhang Jiashun Wang Dong Lu Yi Li Jie Ren Menglu Shen Lei Zhang Jinhai Huang School of Life Sciences Tianjin University

Porcine reproductive and respiratory syndrome virus(PRRSV) shows characteristic antibody-dependent enhancement(ADE) of infection and causes porcine systemic inflammation, which is similar to a type I allergic reaction; however, the role of porcine FceεRI in ADE is still unclear. In this study, the expression of different Fc receptors(Fc Rs) on macrophages was investigated in a PRRSV 3D4/21 cell infection model in the presence or absence of PRRSV antibody. The transcription level of fcc II and FceεRI was significantly up-regulated under PRRSV-antibody complex infection. Internalization and proliferation of PRRSV were promoted by the ADE mechanism when FceεRI was expressed in permissive 3D4/21 cells and the non-permissive cell line HEK 293T. Transcriptome sequencing data showed that the expression levels of AKT,ERK and other signal molecules in the anti-inflammatory pathway were significantly increased, especially in the cells infected with the PRRSV-antibody immune complex. Inflammatory regulatory molecules such as PLA2G6, LOX, TRPM8 and TRPM4 were significantly up-regulated following PRRSV infection but significantly down-regulated in the cells infected with the PRRSV-antibody immune complex. Our results demonstrated that FceεRI could be involved in PRRSV ADE, the antigen presenting process and regulation of the inflammatory response during PRRSV infection, which provides new insights into PRRSV infection mediated by FceεRI and the PRRSV-antibody immune complex.

关键词：过敏反应 fcc 症候群调整繁殖病毒呼吸 PRRSV