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渗氮马氏体不锈钢中crn相析出演化规律的TEM研究

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渗氮马氏体不锈钢中CrN相析出演化规律的TEM研究

Tribological behavior of crn-coated Cr–Mo–V steels used as die materials

北京力学会第30届学术年会

作者：席正中张宏业贺瑞军韩啸刘战伟

马氏体不锈钢的经典氮化会产生压缩残余应力和硬化层。应力的产生与氮扩散过程中相变引起的体积变化直接相关;硬度与MN氮化物的形成有关。本文采用透射电子显微镜(TEM)研究了AISI422马氏体不锈钢离子渗氮过程中渗氮层微观组织的演变过... 详细信息

马氏体不锈钢的经典氮化会产生压缩残余应力和硬化层。应力的产生与氮扩散过程中相变引起的体积变化直接相关;硬度与MN氮化物的形成有关。本文采用透射电子显微镜(TEM)研究了AISI422马氏体不锈钢离子渗氮过程中渗氮层微观组织的演变过程。研究发现马氏体相内部率先溶质原子偏聚区,主要元素为Cr和N元素,随着渗氮进行N浓度的升高,溶质元素析出转化为半共格Cr N相,Cr N相继续生长粗化并发生共格失稳转变为非共格Cr N相。非共格Cr N相也会由原基体中晶界处M23C6转变生成。其中半共格Cr N相析出后会产生共格应变场,这种共格应变场随Cr N相的厚度变化而变化,厚度越大,压应变越大。半共格Cr N相诱导的共格应变场的定量表征为渗氮AISI422马氏体不锈钢力学性能的优化提供了有价值的参考。

关键词：马氏体不锈钢渗氮应变 crn TEM

来源： cnki会议评论

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1394-1402页

作者： Gulsah Aktas Celik Seyda Polat S.Hakan Atapek Kocaeli University Faculty of EngineeringDepartment of Metallurgical and Materials EngineeringUmuttepe Campus41380 KocaeliTurkey

DIN 1.2343 and 1.2367 steels are commonly used as die materials in aluminum extrusion, and single/duplex/multi-coatings enhance their surface properties. The design of an appropriate substrate/coating system is important for improving the tribological performance of these steels under service conditions because the load-carrying capacity of the system can be increased by decreasing the plastic deformation of the substrate. In this study, the tribological behavior of crn-coated Cr–Mo–V steels(DIN 1.2343, 1.2367, and 1.2999 grades) was investigated using different setups and tribological pairs at room and elevated temperatures. The aim of this study was to reveal the wear resistance of a suggested system(1.2999/crn) not yet studied and to understand both the wear and the failure characteristics of coated systems. The results showed that(i) among the steels studied, the DIN 1.2999 grade steel exhibited the lowest friction coefficient because it had the highest load-carrying capacity as a result of secondary hardening at elevated temperatures;(ii) at room temperature, both abrasive tracks and adhesive layers were observed on the worn surfaces; and(iii) a combination of chemical reactions and progressive oxidation caused aluminum adhesion on the worn surface, and the detachment of droplets and microcracking were the characteristic damage mechanisms at high temperatures.

关键词： Cr–Mo–V steels crn coating aluminum extrusion tribological behavior

Effects of Bias Voltage on the Structure and Mechanical Properties of Thick crn Coatings Deposited by Mid-Frequency Magnetron Sputtering

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Plasma Science and Technology 2009年第1期11卷 38-41页

作者：容双全何俊王红军田灿鑫郭立平付德君 Accelerator Lab Department of PhysicsKey Laboratory of Acoustic and Photonic Materials and Devices of Ministry of EducationWuhan University Accelerator Lab Department of PhysicsKey Laboratory of Acoustic and Photonic Materials and Devices of Ministry of EducationWuhan University

Thick crn coatings were deposited on Si （111） substrates by electron source assisted mid-frequency magnetron sputtering working at 40 kHz. The deposition rate, structure, and microhardness of the coatings were strongly influenced by the negative bias voltage （Vb）. The deposition rate reached 8.96 μm/h at a Vb of -150 V. X-ray diffraction measurement revealed strong crn （200） orientation for films prepared at low bias voltages. At a high bias voltage of Vb less than -25 V both crn （200） and （111） were observed. Large and homogeneous grains were observed by both atomic force microscopy and scanning electron microscopy in samples prepared under optimal conditions. The samples exhibited a fibrous microstructure for a low bias voltage and a columnar structure for VD less than -150 V.

关键词： crn middle-frequency magnetron sputtering bias voltage

Morphological effect on electrochemical performance of nanostructural crn

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Chinese Physics B 2021年第12期30卷 625-631页

作者： Zhengwei Xiong Xuemei An Qian Liu Jiayi Zhu Xiaoqiang Zhang Chenchun Hao Qiang Yang Zhipeng Gao Meng Zhang Joint Laboratory for Extreme Conditions Matter Properties Southwest University of Science and TechnologyMianyang 621010China Institute of Electronic Engineering China Academy of Engineering Physics(CAEP)Mianyang 621900China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900China Affiliated Hospital Chengdu University of Traditional Chinese MedicineChengdu 611137China

Size and morphology are critical factors in determining the electrochemical performance of the supercapacitor materials,due to the manifestation of the nanosize ***,different nanostructures of the crn material are prepared by the combination of a thermal-nitridation process and a template ***-temperature nitridation could not only transform the hexagonal Cr_(2)O_(3)into cubic crn,but also keep the template morphology barely *** obtained crn nanostructures,including(i)hierarchical microspheres assembled by nanoparticles,(ii)microlayers,and(iii)nanoparticles,are studied for the electrochemical *** crn microspheres show the best specific capacitance(213.2 F/g),cyclic stability(capacitance retention rate of 96%after 5000 cycles in 1-mol/L KOH solution),high energy density(28.9 Wh/kg),and power density(443.4 W/kg),comparing with the other two *** on the impedance spectroscopy and nitrogen adsorption analysis,it is revealed that the enhancement arised mainly from a high-conductance and specific surface area of crn *** work presents a general strategy of fabricating controllable crn nanostructures to achieve the enhanced supercapacitor performance.

关键词： crn supercapacitors metal nitride nanostructures

Tribological properties of crn coating deposited on 20CrMo against tin bronze

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Science China(Technological Sciences) 2018年第11期61卷 1713-1722页

作者： LIU JiLiang LIAO RiDong XIE GuoXin XIANG JianHua LUO Jun LIAO Bin LIU QingYi School of Mechanical Engineering Beijing Institute of TechnologyBeiiing 100081China Beijing Liang Xin Technology Co. Ltd.Beijing 100081China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Beijing Radiation Center Beijing 100875China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China State Key Laboratory of Engine Reliability Weichai Power Co.Ltd.Weifang 261001China

A crn coating was deposited on the piston pin material 20CrMo. The tribological properties of 20CrMo and crn coating against tin bronze QSn7-0.2 were compared by pin-on-disk tests under dry friction and oil lubrication, respectively. The cross-sectional morphologies and structures of the coating were characterized through scanning electron microscopy and X-ray diffraction. The hardness, elastic modulus, and adhesion strength of the coating were tested through nano-hardness and scratch tests. The wear tracks were tested with an optical profilometer, and wear volume was calculated. Under dry friction conditions, the crn coating exhibited a significantly stable friction coefficient and a relatively lower wear rate against QSn7-0.2 at various temperatures compared with 20CrMo. The wear rate decreased by 98.5% at 700°C. Under poly-alpha-olefine lubrication, the crn coating reduced the load effect on the friction coefficient. Under engine oil 5 W40 lubrication, the crn coating improved the tribological properties under high speed and heavy load conditions. Simultaneously, the crn coating changed the friction and heat flow with increasing temperature.

关键词： crn coating tribological properties piston pin friction coefficient wear rate

Microstructure and Mechanical Properties of crn Films Deposited by Inductively Coupled Plasma Enhanced Radio Frequency Magnetron Sputtering

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Plasma Science and Technology 2008年第3期10卷 340-343页

作者：刘峰孟月东任兆杏舒兴胜 Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China

crn films have been synthesized on Si（100） wafer by inductively coupled plasma （ICP）-enhanced radio frequency （RF） magnetron sputtering. The effects of ICP power on microstructure, crystal orientation, nanohardness and stress of the crn films have been investigated. With the increase of ICP power, the current density at substrate increases and the films exhibit denser structure, while the DC self-bias of target and the deposition rate of films decrease. The films change from crystal structure to amorphous structure with the increase of ICP power. The measured nanohardness and the compressive stress of films reach the topmost at ICP power of 150 W and 200 W, respectively. The mechanical properties of films show strong dependence on the crystalline structure and the density influenced by the ICP power.

关键词： inductively coupled plasma (ICP) RF magnetron sputtering crn microstructure nanohardness stress

Structural,electronic,and magnetic properties of crn under high pressure

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Chinese Physics B 2011年第7期20卷 356-361页

作者：蔺何曾雉 Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of Sciences Institute of Applied Chemistry Xinjiang University Graduate University of the Chinese Academy of Sciences

The structural, electronic and magnetic properties of crn under high pressure are investigated by first-principles calculations. The antiferromagnetic orthorhombic structure is identified to be the preferred ground state structure. It possesses a bulk modulus of 252.8 GPa and the nonzero magnetic moment of 2.33 μB per Cr ion, which agree well with the experimental results. crn undergoes structural and magnetic transitions from an antiferromagnetic rocksalt structure to a non-magnetic Pnma phase at 132 GPa. Under compression, the magnetic moment of the Cr ion reduces rapidly near the equilibrium and phase transition point, and the distribution of the density of states is broadened, but the form of overlap between the orbitals of Cr d and N p remains unchanged. The broadening of the band induces spin flipping, which consequently results in the smaller magnetic moment of the Cr ion.

关键词： crn pressure electronic property magnetic property

Interface-enhanced thermoelectric output power in crn/SrTiO_(3-x) heterostructure

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Journal of Energy Chemistry 2022年第1期31卷 16-22,I0002页

作者： Xueying Wan Xiaowei Lu Lin Sun Mingyu Chen Na Ta Wei Liu Qi Chen Liwei Chen Jian He Peng Jiang Xinhe Bao State Key Laboratory of Catalysis CAS Center for Excellence in NanoscienceDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina i-Lab Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123jiangsuChina Department of Physics and Astronomy Clemson UniversityClemson 29634-0978USA

Thermoelectric devices enable direct conversion between thermal and electrical *** studies have indicated that the thin film/substrate heterostructure is effective in achieving high thermoelectric performance via decoupling the Seebeck coefficient and electrical conductivity otherwise adversely inter-dependent in homogenous bulk ***,the mechanism underlying the thin film/substrate heterostructure thermoelectricity remains *** addition,the power output of the thin film/substrate heterostructure is limited to the nanowatt scale to date,falling short of the practical application ***,we fabricated the crn/SrTiO_(3-x) heterostructures with high thermoelectric output power and outstanding thermal *** varying the crn film thickness and the reduction degree of crn/SrTiO_(3-x) substrate,the optimized power output and the power density have respectively reached 276μWand 10^(8) mW/cm^(2) for the 30 nm crn film on a highly reduced surface of crn/SrTiO_(3-x) under a temperature difference of 300 *** performance enhancement is attributed to the crn/crn/SrTiO_(3-x) heterointerface,corroborated by the band bending as revealed by the scanning Kelvin probe *** results will stimulate further research efforts towards interface thermoelectrics.

关键词： SrTi0_(3-x) crn Heterostructure Interface thermoelectrics Thin film

Formation of nanocrystalline microstructure in arc ion plated crn films

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 73-77页

作者： Qi-min WANG Se-Hun KWON Kwang-Ho KIM National Core Research Center for Hybrid Materials Solution Pusan National University Busan 609-735 Korea School of Materials Science and Engineering Pusan National University Busan 609-735 Korea

Applying negative bias voltages caused significant microstructure changes in arc ion plated crn films. Nanocrystalline microstructures were obtained by adjusting the negative bias voltage. Structural characterizations of the films were carried out using X-ray diffractometry (XRD) and high-resolution transmission electron microscopy (HR-TEM). The results indicated that increasing ion bombardment by applying negative bias voltages resulted in the formation of defects in the crn films, inducing microstructure evolution from micro-columnar to nanocrystalline. The microhardness and residual stresses of the films were also affected. Based on the experimental results, the evolution mechanisms of the film microstructure and properties were discussed by considering ion bombardment effects.

关键词： crn thin films deposition microstructure arc ion plating ion bombardment