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Microstructure and Growth Kinetics of Silicide Coatings for TiAl Alloy

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Journal of Wuhan University of Technology(Materials Science) 2017年第2期32卷 245-249页

作者：黄磊吴向清 xie faqin WANG Su School of Aeronautics Northwestern Polytechnical University

In order to improve the oxidation resistance of Ti Al alloy, silicide coatings were prepared by pack cementation method at 1273, 1323, and 1373 K for 1-3 hours. Scanning electron microscopy（SEM）, energy dispersive spectrometry（EDS） and X-ray diffraction（XRD） were employed to investigate the microstructures and phase constitutions of the coatings. The experimental results show that all silicon deposition coatings have multi-layer structure. The microstructure and composition of silicide coatings strongly depend on siliconizing temperatures. In order to investigate the rate controlling step of pack siliconizing on Ti Al alloy, coating growth kinetics was analyzed by measuring the mass gains per unit area of silicided samples as a function of time and temperature. The results showed that the rate controlling step was gas-phase diffusion step and the growth rate constant（k） ranged from 1.53 mg^2/（cm^4·h^2） to 2.3 mg^2/（cm^4·h^2）. Activation energy（Q） for the process was calculated as 109 k J/mol, determined by Arrhenius＇ equation： k = k0 exp[–Q/（RT）].

关键词： pack cementation coating titanium aluminide siliconizing kinetics activation energy rate controlling step

Slurry erosion behaviors of P110 steel and chromizing coating in liquid-solid two-phase flow

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Science China(Technological Sciences) 2013年第6期56卷 1415-1423页

作者： LIN NaiMing xie faqin ZOU JiaoJuan TANG Bin Taiyuan University of Technology Northwestern Polytechnical University

A chromizing coating was formed on P110 oil casing tube steel (P110 steel) via pack cementation to improve its performance and increase the lifetime during operation. The slurry erosion behaviors of the P110 steel substrate and the chromizing coating were assessed in a liquid-solid two-phase flow condition. The results showed that the obtained coating exhibited higher surface hardness, lower mass loss, and lower slurry erosion rate than those of P110 steel. The chromizing treatment has significantly improved the surface hardness and slurry erosion resistance of P110 steel.

关键词： P110钢液固两相流冲蚀行为铬涂层泥浆表面硬度侵蚀速率石油套管钢

Application of Artificial Neural Network in Predicting the Thickness of Chromizing Coatings on P110 Steel

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Journal of Wuhan University of Technology(Materials Science) 2013年第1期28卷 196-201页

作者：林乃明 xie faqin ZOU Jiaojuan WANG Hefeng TANG Bin Research Institute of Surface Engineering Taiyuan University of Technology School of Aeronautics Northwestern Polytechnical University

A series of rare earth （RE） dispersed chromizing coatings were produced on P 110 steel by pack cementation. The orthogonal array design （OAD）was applied to set the experiments. An artificial neural network （ANN） approach is employed to predict the thickness values of the obtained chromizing coatings based on the OAD tests results. The results revealed that the built model was reliable, the thickness values of chromizing coatings were well predicted at selected process parameters, and the predicted error lied in rational range.

关键词： artificial neural network thickness rare earth chromizing coating P110 steel

Wear and Corrosion Resistance of Electroless Plating Ni-P Coating on P110 Steel

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Journal of Wuhan University of Technology(Materials Science) 2015年第3期30卷 622-625页

作者：林乃明 ZHOU Peng ZOU Jiaojuan xie faqin TANG Bin Research Institute of Surface Engineering Taiyuan University of Technology School of Aeronautics Northwestern Polytechnical University

In order to improve the surface performance and increase the lifetime of P 110 oil casing tube steel during operation, electroless plating was conducted to form Ni-P coating onto its surface. The surface morphology/element distribution and phase constitution of the Ni-P coating were analyzed using scanning electron microscope （SEM） equipped with energy dispersive spectrometry （EDS） and X-ray diffraction （XRD）. Tribological and electrochemical measurement tests were applied to investigate the wear and corrosion resistance of P110 steel and the Ni-P coating. The results showed that a uniform and compact, high phosphorous Ni-P coating was formed. The obtained Ni-P coating indicated certain friction-reduction effect and lower mass loss during friction-wear tests. The Ni-P coating also exhibited higher corrosion resistance in comparison with bared P 110 steel. The obtained N i-P coating has significantly improved the surface performance of P110 steel.

关键词： wear corrosion electroless plating Ni-P coating P110 steel

Microwave absorption properties of Ni/C@SiC composites prepared by precursor impregnation and pyrolysis processes

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Defence Technology（防务技术） 2023年第3期21卷 94-102页

作者： Xinli Ye Junxiong Zhang Zhaofeng Chen Junfeng Xiang Yun Jiang faqin xie Xiaomin Ma School of Civil Aviation Northwestern Polytechnical UniversityXi'an710072PR China Suzhou Qinyun Fiber Assemblies Technology Co.LTD Suzhou215400PR China School of Textile and Clothing Nantong UniversityNantong226019PR China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211106PR China College of Textile Science and Engineering Jiangnan UniversityWuxi214122PR China National Equipment New Material&Technology(Jiangsu)Co.LTD Suzhou215400PR China

In the present study,the unique three-dimensional graphene coated nickel(Ni/C)foam reinforced silicon carbide(Ni/C@SiC)composites were first obtained via the precursor impregnation and pyrolysis(PIP)processes.The microstructure images indicated that the SiC fillers were successfully prepared in the skeleton pores of the Ni/C foam.The influence of the PIP cycles on the microwave absorption performances was researched,and the results indicated that after the primary PIP process,Ni/C@SiC-I possessed the optimal microwave absorbing performance with a minimum reflection loss(RL)of-25.87 d B at 5.28 GHz and 5.00 mm.Besides,the RL values could be below-10.00 dB from 5.88 GHz to 7.74 GHz when the corresponding matching thickness was 3.85 mm.However,the microwave absorption properties of Ni/C@SiC-II and Ni/C@SiC-Ⅲwere tremendously degraded as the PIP times increased.At last,the electromagnetic parameter,dielectric loss,attenuation constant as well as impedance matching coefficient were further investigated to analyze the absorbing mechanism,which opened a new path for the certain scientific evaluation of the absorbing materials and had extremely important to the defence technology.

关键词： composites Ni/C absorption

An investigation on supercooling directional solidification process of Cu-Ni single phase alloy

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Chinese Science Bulletin 2000年第2期45卷 131-134页

作者： faqin xie Jinshan Li Hengzhi Fu Northwestern Polytech Univ State Key Lab Solidificat Proc Xian 710072 Peoples R China

Supercooling directional solidification (SDS) is put fotward by combination of melt supercooling and conventional solidification by application of supercooling inheritance. On the self-designed SDS equipment, SDS of Cu-Ni alloy was achieved successfully The results are as follows f (i) The primary arm spacing is about 30 μm, the growth of secondary arms are strongly suppressed. The primary arm spacing is nearly the same as LMC method (GL=25 K/mm, V=500 pm/s), the primary stems are straight, fine and completed. with an inclination angle of about 5.8° (ii) A semi-quantitative T-T model is brought fotward to describe the dendrite growth rate V vs. undercooling AT The prediction of T-T model agrees well with experimental results. The formation of fine equiaxed dendrites, transition region and dendrite region can be explained successfully by △T-V-x relation of T-T model.

关键词： alloy melt superrooling dieretional soudification supereooling directional solidification.

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γ-TiAl合金高温抗氧化涂层研究进展

稀有金属材料与工程 2022年第10期51卷 3929-3936页

作者：屈静谢发勤吴向清高广睿西北工业大学陕西西安710072 西安赛福斯材料防护有限责任公司陕西西安710200

TiAl基合金具有密度低、弹性模量大、比强度高等特点,是航空发动机用镍基高温合金最有竞争力的替代材料之一。本文从扩散渗、激光熔覆、双辉等离子渗金属、大气等离子喷涂、物理气相沉积等制备技术出发,概述了TiAl基合金高温抗氧化涂层... 详细信息

TiAl基合金具有密度低、弹性模量大、比强度高等特点,是航空发动机用镍基高温合金最有竞争力的替代材料之一。本文从扩散渗、激光熔覆、双辉等离子渗金属、大气等离子喷涂、物理气相沉积等制备技术出发,概述了TiAl基合金高温抗氧化涂层的研究进展,并根据航空发动机性能持续提高对材料的要求,提出了实现TiAl合金在先进发动机上应用的研究方向。

关键词： TiAl基合金高温抗氧化制备技术涂层

氧化热处理温度对多孔镍泡沫微观结构及吸波性能的影响

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复合材料学报 2022年第8期39卷 3794-3803页

作者：叶信立张俊雄项俊锋蒋云谢发勤西北工业大学民航学院西安710072 苏州勤耘纤维集合体科技有限公司苏州215400 南通大学纺织服装学院南通226019 江南大学纺织科学与工程学院无锡214122

为了探究多孔镍泡沫在电磁污染环境应用的可能性,根据多孔镍泡沫在空气下的热重曲线图,采用不同氧化热处理温度对其进行高温处理,借助TG-DSC、XRD、SEM、矢量网络分析仪研究氧化热处理温度对多孔镍泡沫的微观结构和电磁波吸收性能的影... 详细信息

为了探究多孔镍泡沫在电磁污染环境应用的可能性,根据多孔镍泡沫在空气下的热重曲线图,采用不同氧化热处理温度对其进行高温处理,借助TG-DSC、XRD、SEM、矢量网络分析仪研究氧化热处理温度对多孔镍泡沫的微观结构和电磁波吸收性能的影响关系。结果表明,当氧化热处理温度超过600℃时,多孔镍泡沫骨架表面产生明显变化,当氧化热处理为900℃时,表面形成大量孔洞,而当氧化热处理温度到达1200℃时,表面呈熔融状。通过物相分析表明,随着氧化热处理温度升高,多孔镍泡沫骨架表面生成氧化镍。对X波段的电磁吸波性能进行测试可以发现,经900℃氧化热处理得到的多孔镍泡沫具有最优异的微波吸收性能,并在10.88 GHz处反射损耗到达最小值−19.66 dB,表明一定的氧化热处理可以有效改善多孔镍泡沫的吸波性能。

关键词：多孔镍泡沫氧化热处理微观结构吸波性能反射损耗

温度对TiAl合金及SiC配副摩擦磨损性能的影响

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稀有金属材料与工程 2017年第2期46卷 538-542页

作者：李涌泉谢发勤西北工业大学陕西西安710072 北方民族大学宁夏银川750021

通过对TiAl合金与SiC配副在20,300和600℃下的摩擦磨损性能研究,分析了摩擦系数,磨损率和磨损形貌随温度的变化规律,探讨了磨损机制。结果表明:在实验温度条件下,TiAl合金的磨损率随温度的增大而增大。在20℃下TiAl合金主要为犁削磨损... 详细信息

通过对TiAl合金与SiC配副在20,300和600℃下的摩擦磨损性能研究,分析了摩擦系数,磨损率和磨损形貌随温度的变化规律,探讨了磨损机制。结果表明:在实验温度条件下,TiAl合金的磨损率随温度的增大而增大。在20℃下TiAl合金主要为犁削磨损、磨粒磨损,随着温度的升高,出现氧化磨损,当温度增加到600℃时,氧化磨损严重;而SiC配副在20℃下的磨损率显著高于300及600℃下的磨损率,这是由于随温度的增加,SiC球的破坏机制由沿晶断裂向剝层磨损转变。

关键词： TiAl合金 SiC配副磨损