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无序态(Co,Fe)_3V应变-时效硬化的微观机制

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金属学报 1992年第11期28卷 A506-A512页

作者：林一坚 s.gialanella R.W.CAHN 上海钢铁研究所应用基础部工程师上海200940 意大利特兰托大学英国剑桥大学

本文通过透射电镜观察确定:无序态(Co_(78)Fe_(22))_3V合金的应变-时效硬化是由于冷变形位错组织在退火中随着有序化进程转变为特别的位错-层错网络——位错在各{111}面上扩展为层错,通过{111}面相交线上偏位错反应互相连接,发展为以层... 详细信息

本文通过透射电镜观察确定:无序态(Co_(78)Fe_(22))_3V合金的应变-时效硬化是由于冷变形位错组织在退火中随着有序化进程转变为特别的位错-层错网络——位错在各{111}面上扩展为层错,通过{111}面相交线上偏位错反应互相连接,发展为以层错四面体为小胞的密集网络,有序态(Co_(78)Fe_(22))_3V合金具有很低的{111}面层错能和相对较高且各向同性的反相畴界能,因此,该合金在高温下维持高强度的微观机制很可能不是Kear-Wilsdof障碍,而是Lomer-Cottrell障碍。

关键词： (Co,Fe)3V 应变时效硬化堆垛层错

(Co_(78)Fe_(22))_3V中层错与反相畴界的相互作用

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上海钢研 1996年第5期 1-7页

作者：林一坚 s.gialanella R.W.Cahn 意大利托兰多大学英国剑桥大学

本文比较了淬火无序态(Co_(78)Fe_(22))_3V在经过冷加工然后退火和未经过冷加工直接退火两种情况下的显微组织,对于无序-有序转变过程中形成稳定层错的机制提出了与前人不同的看法,认为是位移矢量为1/6〈112〉的层错与位移矢量为1/2〈11... 详细信息

本文比较了淬火无序态(Co_(78)Fe_(22))_3V在经过冷加工然后退火和未经过冷加工直接退火两种情况下的显微组织,对于无序-有序转变过程中形成稳定层错的机制提出了与前人不同的看法,认为是位移矢量为1/6〈112〉的层错与位移矢量为1/2〈110〉的反相畴界反应生成位移矢量为1/3〈112〉的超点阵内禀层错(sIsF)的结果。在冷加工引入大量位错的情况下,位错分解为层错,并与反相畴界反应,生成密集的sIsF层错四面体胞群,在720℃48h退火后仍保持几十纳米的细小尺寸。

关键词：金属间化合物层错反相畴界

(Co,Fe)_3V有序转变中位错组态的变化及其硬化效应

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上海钢研 1992年第5期 35-42,51页

作者：林一坚 s.gialanella R.W.Cahn 上海钢铁研究所 University of Tren to Italy University of Cambridge U. K.

金属间化合物(Co_(78)Fe_(22))_3V从临界温度之上淬火可得无序态,冷加工后在退火中表现出很强的硬化效应,其硬化幅度远大于单纯的有序强化。通过TEM观察确定,这种应变时效硬化是由于冷加工位错组织在退火中随着有序化进程转变为一种特... 详细信息

金属间化合物(Co_(78)Fe_(22))_3V从临界温度之上淬火可得无序态,冷加工后在退火中表现出很强的硬化效应,其硬化幅度远大于单纯的有序强化。通过TEM观察确定,这种应变时效硬化是由于冷加工位错组织在退火中随着有序化进程转变为一种特别的位错一层错网络的结果:位错普遍扩展为{111}面层错,通过{111}面相交线上偏位错反应生成Lomer-Cottrell结线而互相联结,发展为以层错四面体为小胞的密集网络。形成这种特殊位错组织是由于在有序转变中层错能发生急剧下降和位错组态出现相应调整的结果。实验结果表明,有序(Co_(78)Fe_(22))_3V的层错能很低而反相畴界能较高且各向同性,因此,这种有序合金的屈服应力随温度上升而提度的机制不可能是通常认为的Keow-Wilsdof障碍,而可能是Lomev-Cottfell障碍。

关键词：金属互化物有序转变位错硬化

纳米结构FeAl合金无序和热恢复过程中的组织、力学和磁性能

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上海钢研 2001年第3期 59-62页

作者： X.Amils J.Nogues s.surinach J.s.Munoz L.Lutterotti s.gialanella M.D.Baro 王景成

本文研究了经球研磨和退火Fe-40Al％B2合金的微观组织、力学和磁性能。它的无序过程的特征是使合金产生硬化和顺磁-铁磁转变,主要决定于晶粒细化和反位缺陷的形成;再有序过程使纳米晶合金连续软化和恢复到顺磁态,它基本上由反位缺陷的... 详细信息

本文研究了经球研磨和退火Fe-40Al％B2合金的微观组织、力学和磁性能。它的无序过程的特征是使合金产生硬化和顺磁-铁磁转变,主要决定于晶粒细化和反位缺陷的形成;再有序过程使纳米晶合金连续软化和恢复到顺磁态,它基本上由反位缺陷的湮没控制。微观组织、力学和磁性能之间的关联使磁性测量成了一个很好的研究FeAl纳米合金微结构和力学状态的非破坏工具。

关键词：热恢复组织力学性能磁性能金属间化合物 FeAl合金纳米合金

Pin-on-disc study of dry sliding behavior of Co-free HVOFcoated disc tested against different friction materials

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Friction 2021年第5期9卷 1242-1258页

作者： Matteo FEDERICI Cinzia MENAPACE Alessandro MANCINI Giovanni sTRAFFELINI stefano gialanella Department of Industrial Engineering University of TrentoTrento 32122Italy Brembo s.p.A. StezzanoBergamo 24040Italy

The dry sliding behavior of three commercial friction materials(codenamed FM1,FM2,and FM3)tested against a Co‐free cermet coating produced by high‐velocity oxy‐fuel(HVOF)on gray cast‐iron discs is ***1 is a conventional low‐metallic friction material,FM2 is developed for using against HVOF‐coated discs,and FM3 is a Cu‐free friction material with a low content of abrasives and a relatively high concentration of steel *** the tribological evaluation,they are tested on a pin‐on‐disc(PoD)test rig against Co‐free HVOF‐coated discs,with particular attention to the running‐in stage,which is fundamental for the establishment of a friction layer between the two mating surfaces,i.e.,the pin and *** PoD tests are performed at room temperature(RT)and a high temperature(HT)of 300℃.At RT,all materials exhibit a long running‐in *** HT,no running‐in is observed in FM1 and FM2,whereas a shorter running‐in period,with respect to the RT case,is observed in FM3 followed by the attainment of a comparatively high coefficient of *** RT,the pin wear is mild in all cases but severe at ***3 shows the lowest wear rate at both ***,the coated disc shows no wear when sliding against the FM3 friction *** the results are interpreted considering the microstructural characteristics of the friction layers formed on the sliding *** findings of the present study provide insights into reducing wear in braking system components and hence reducing environmental particulate matter emissions from their wear,through the use of disc coatings.

关键词： friction materials sliding wear high‐velocity oxy‐fuel(HVOF)coatings pin‐on‐disc(PoD)testing

Green and low temperature synthesis of nanocrystalline transition metal ferrites by simple wet chemistry routes

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Nano Research 2014年第7期7卷 1027-1042页

作者： stefano Diodati Luciano Pandolfo Andrea Caneschi stefano gialanella silvia Gross Istituto per I'Energetica e le In terfasi IENI-CNR and INSTM UdR di Padova via Marzolo 11-35131 Padova Italy Dipartimento di scienze Chimiche Universit& degli Studi di Padova via Marzolo 11-35131 Padova Italy Laboratory of Molecular Magnetism LAMM Dipartimento di Chimica e UdR INSTM di Firenze Polo Scientifico Via della Lastruccia 3 50019 Sesto Fiorentino (FI) Italy Dipartimen to di Ingegneria Industriale Universita degli Studi di Tren to via Mesiano 771-38123 Trento Italy

Crystalline and nanostructured cobalt （CoFe2O4）, nickel （NiFe2O4）, zinc （ZnFe2O4） and manganese （MnFe2O4） spinel ferrites are synthesized with high yields, crystallinity and purity through an easy, quick, reproducible and low-temperature hydrothermal assisted route starting from an aqueous suspension of copredpitated metal oxalates. The use of water as a reaction medium is a further advantage of the chosen protocol. Additionally, the zinc spinel is also prepared through an alternative route combining copredpitation of oxalates from an aqueous solution with thermal decomposition under reflux conditions. The nanocrystalline powders are obtained as a pure crystalline phase already at the extremely low tem- perature of 75 ℃ and no further thermal treatment is needed. The structure and microstructure of the prepared materials is investigated by means of X-ray powder diffraction （XRPD）, while X-ray photoelectron spectroscopy （XPs） and inductively coupled plasma-atomic emission spectroscopy （ICP-AEs） analyses are used to gain information about the surface and bulk composition of the samples, respectively, confirming the expected stoichiometry. To investigate the effect of the synthesis protocol on the morphology of the obtained ferrites, transmission electron microscopy （TEM） observations are performed on selected samples. The magnetic properties of the cobalt and manganese spinels are also investigated using a superconducting quantum device magnetometer （sQUID） revealing hard and soft ferrimagnetic behavior, respectively.

关键词： ferrites hydrothermal low temperature wet chemistry green

Characterization of ultrafine particles from hardfacing coated brake rotors

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Friction 2023年第1期11卷 125-140页

作者： Yezhe LYU Ankur sINHA Ulf OLOFssON stefano gialanella Jens WAHLsTRÖM Department of Mechanical Engineering sciences Lund UniversityLund SE-22100Sweden Department of Machine Design KTH Royal Institute of TechnologyStockholm SE-10044Sweden Department of Industrial Engineering University of TrentoTrento 38123Italy

Automotive brake rotors are commonly made from gray cast iron(GCI).During usage,brake rotors are gradually worn off and periodically ***,replaced brake rotors are mostly remelted to produce brand-new cast iron products,resulting in a relatively high energy consumption and carbon footprint into the *** addition,automotive brakes emit airborne *** of the emitted particles are categorized as ultrafine,which are sized below 100 nm,leading to a series of health and environmental *** this study,two surface treatment techniques are applied,ie.,high-velocity oxygen fuel(HVOF)and laser cladding(LC),to overlay wear-resistant coatings on conventional GCI brake rotors in order to refurbish the replaced GCI brake rotor and to avoid the remelting *** two coating materials are evaluated in terms of their coefficient of friction(CoF),wear,and ultrafine particle emissions,by comparing them with a typical GCI brake *** results show that the CoF of the HVOF disc is higher than those of the GCI and LC ***,HVOF disc has the lowest wear rate but results in the highest wear rate on the mating brake pad *** LC disc yields a similar wear rate as the GCI *** ultrafine particles from the GCI and LC discs appeared primarily in round,chunky,and flake *** HVOF disc emits unique needle-shaped *** the ultrafine particle range,the GCI and HVOF discs generate particles that are primarily below 100 nm in the running-in period and 200 nm in the steady ***,the LC disc emitted particles that are primarily~200 nm in the entire test run.

关键词： ultrafine particle high-velocity oxygen fuel laser cladding brake particle size distribution particle morphology

Hepatic pseudotumor associated with strongyloides infection:A case report

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World Journal of Hepatology 2023年第12期15卷 1338-1343页

作者： Jessica P gialanella Tyler steidl Kokkola Korpela Miral s Grandhi Russell C Langan H Richard Alexander Rachel M Hudacko Brett L Ecker Department of surgical Oncology Rutgers Cancer Institute of New JerseyNew BrunswickNJ 08901United States Rutgers New Jersey Medical school NewarkNJ 07103United States Department of Infectious Disease Cooperman Barnabas Medical CenterLivingstonNJ 07039United States Department of Pathology and Labratory Medicine Rutgers Robert Wood Johnson Medical SchoolNew BrunswickNJ 08901United States

BACKGROUND strongyloides sterocoralis is a parasitic infection caused by a roundworm that is transmitted through soil contaminated with *** can infrequently cause hepatic abscesses in immunocompromised patients and is rarely reported to form hepatic lesions in immunocompetent *** sUMMARY We present a case study of a 45-year-old female who presented with right upper quadrant abdominal pain and constitutional symptoms for several *** imaging identified several malignant-appearing liver *** investigation,including serological testing and histopathologic examination,revealed the presence of serum strongyloides antibodies and hepatic granulomas with extensive *** treatment with ivermectin for 2 wk,there was complete resolution of the liver lesions and associated *** This case highlights the importance of considering parasitic infections,such as strongyloides,in the differential diagnosis of hepatic *** recognition and appropriate treatment can lead to a favorable outcome and prevent unnecessary invasive *** awareness among clinicians is crucial to ensure the timely diagnosis and management of such cases.

关键词： Hepatic tumor Liver mass strongyloides sterocoralis Parasitology Case report