期刊文献+
共找到1,385篇文章
< 1 2 70 >
每页显示 20 50 100
Recent Advances in Interface Modification of Cu/graphite Composites and Layered Ternary Carbides of Modified Layer Candidate
1
作者 WEI Hongming LI Mingchao +4 位作者 LI Xiaoya ZHAN Wenyi LI Feiyang DAI Yanzhang ZOU Jianpeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1061-1072,共12页
We review the fundamental properties and significant issues related to Cu/graphite composites.In particular,recent research on the interfacial modification of Cu/graphite composites is addressed,including the metal-mo... We review the fundamental properties and significant issues related to Cu/graphite composites.In particular,recent research on the interfacial modification of Cu/graphite composites is addressed,including the metal-modified layer,carbide-modified layer,and combined modified layer.Additionally,we propose the use of ternary layered carbide as an interface modification layer for Cu/graphite composites. 展开更多
关键词 Cu/graphite composites interfacial bonding surface modification WETTABILITY layered ternary carbides
下载PDF
Research Progress of High Entropy Carbides
2
作者 QIN Ying DU Zhanyuan +1 位作者 LIU Xinzhuang YU Jinghua 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1440-1448,共9页
High entropy carbides (HECds) are multi-component carbides consisting of transition metal carbides.HECds are generally composed of five or more metal cations of the equal or near-equal substances,obtaining a single cr... High entropy carbides (HECds) are multi-component carbides consisting of transition metal carbides.HECds are generally composed of five or more metal cations of the equal or near-equal substances,obtaining a single crystal structure.HECds have great potentials for future applications due to excellent mechanical,antioxidant and thermal properties.Due to their complex crystal structures and lattice distortion,computer simulations are widely used to efficiently associate the properties of HECds with the corresponding microstructures.In response to the development of HECds,this article provides an overview of the basic design,preparation process and properties of HECds. 展开更多
关键词 high entropy carbides(HECds) computer simulation PROCESSING PROPERTIES
下载PDF
Pulsed laser interference patterning of transition-metal carbides for stable alkaline water electrolysis kinetics
3
作者 Yewon Oh Jayaraman Theerthagiri +3 位作者 Ahreum Min Cheol Joo Moon Yiseul Yu Myong Yong Choi 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期65-80,共16页
We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed ... We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed laser ablation of Co,Fe,Ti,and Mo metals in acetone.The interaction between carbon s-p-orbitals and metal d-orbitals causes a redistribution of valence structure through charge transfer,leading to the formation of surface defects as observed by X-ray photoelectron spectroscopy.These defects influence the evolved TMCs,making them effective for hydrogen and oxygen evolution reactions(HER and OER)in an alkaline medium.Co_(3)C with more oxygen affinity promoted CoO(OH)intermediates,and the electrochemical surface oxidation to Co_(3)O_(4)was captured via in situ/operando electrochemical Raman probes,increasing the number of active sites for OER activity.MoC with more d-vacancies exhibits strong hydrogen binding,promoting HER kinetics,whereas Fe_(3)C and TiC with more defect states to trap charge carriers may hinder both OER and HER activities.The results show that the assembled membrane-less electrolyzer with Co_(3)C∥Co_(3)C and MoC∥MoC electrodes requires~2.01 and 1.99 V,respectively,to deliver a 10 mA cm−2 with excellent electrochemical and structural stability.In addition,the ascertained pulsed laser synthesis mechanism and unit-cell packing relations will open up sustainable pathways for obtaining highly stable electrocatalysts for electrolyzers. 展开更多
关键词 ACETONE H_(2)and O_(2)evolution reactions pulsed laser ablation surface defects transition-metal carbides water electrolyzer
下载PDF
Comparative Study on Microstructure and Mechanical Properties of Coarse-grained WC-based Cemented Carbides Sintered with Ultrafine WC or (W+C) as Additives
4
作者 于淞百 闵凡路 +6 位作者 LI De NOUDEM Guillaume Jacques ZHANG Hailong MA Jichang ZHAO Kui YAO Zhanhu 张建峰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期399-409,共11页
The effects of ultrafine WC(WC_(UF),0.5μm) or W(1μm) and C(0.3μm)(W+C)_(UF) additives on the densification,microstructure and mechanical properties of coarse-grained cemented carbides were compared systematically.O... The effects of ultrafine WC(WC_(UF),0.5μm) or W(1μm) and C(0.3μm)(W+C)_(UF) additives on the densification,microstructure and mechanical properties of coarse-grained cemented carbides were compared systematically.Overall,the cemented carbides with WC_(UF)/(W+C)_(UF) additives are almost fully densification to be higher than 99%,and the average grain size is kept above 2.8μm.The WC_(UF) additive assists grains to(truncated)trigonal prism shape by two dimensional(2D) growth,whereas the(W+C)_(UF) additive assists grains to rounded shape by three dimensional(3D) growth,lowers WC contiguity and increases face-centered-cubic Co.The hardness and bending strength of(75WC_(C)-15WC_(UF))-10Co are 86.6 HRA and 2 272 MPa,respectively,both higher than those of(75WC_(C)-15(W+C)_(UF))-10Co,which could be ascribed to the enhanced densification and unblemished grains.However,the fracture toughness of the(75WC_(C)-15(W+C)_(UF))-10Co is 23.5 MPa·m^(1/2),higher than that of the(75WC_(C)-15WC_(UF))-10Co due to the uniform WC-Co structure and flexible binder phase. 展开更多
关键词 coarse-grained WC-based cemented carbide ultrafine WC ultrafine(W+C) microstructure mechanical properties
下载PDF
Effects of Ta C on microstructure and mechanical properties of coarse grained WC-9Co cemented carbides 被引量:18
5
作者 苏伟 孙业熙 +2 位作者 杨海林 张贤其 阮建明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1194-1199,共6页
Coarse grained WC-9Co cemented carbides with 0-1.0% TaC(mass fraction) were fabricated by HIP-sintering and gas quenching. The effects of TaC on the microstructures and mechanical properties were investigated using sc... Coarse grained WC-9Co cemented carbides with 0-1.0% TaC(mass fraction) were fabricated by HIP-sintering and gas quenching. The effects of TaC on the microstructures and mechanical properties were investigated using scanning electron microscopy(SEM), energy dispersive X-ray analysis(EDS), X-ray diffractometry(XRD) and mechanical properties tests. The results show that the maximum values of hardness and strength are HV 1124 and 2466 MPa respectively when 0.4% TaC is added. When the content of TaC is more than 0.6%, the grain size of WC is no longer affected by the amount of TaC, and(W,Ta)C occurs as well. Moreover, the strength and fracture toughness increase and the(Ta+W) content decreases with the increase of TaC content. The dependence of(Ta+W) content on the mechanical properties indicates that(Ta+W) content in Co should be decreased as low as possible to improve the mechanical properties of coarse grained WC-TaC-9Co cemented carbides with the microstructure of WC+γ two phase regions. 展开更多
关键词 coarse grained WC–9Co cemented carbides Ta C Ta content W content
下载PDF
Elastoplastic response of functionally graded cemented carbides due to thermal loading
6
作者 黄自谦 李传新 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期463-466,共4页
Finite dement formulations are used to simulate the evolution of the elastoplastic response of functionally graded cemented carbides (FGCC) due to thermal loading. The geometry of specimens is an axisymmetric solid ... Finite dement formulations are used to simulate the evolution of the elastoplastic response of functionally graded cemented carbides (FGCC) due to thermal loading. The geometry of specimens is an axisymmetric solid cylinder with a two-dimensional gradient. The elastoplastic constitutive relationship is developed by constraint factors. Numerical results show that compressive stresses occur in the surface zone and tensile stresses in the cobalt rich zone when the temperature drops from the initial stress-free temperature of 800 to 0℃. The maximum value of the surface compressive stress is 254 MPa and the maximum value of the tensile stress is 252 MPa in the cobalt rich zones. When the cobalt concentration difference in the specimens is equal to or greater than 0.3, there is pronounced plastic flow in cobalt rich zone. When the temperature heats up from 0 to 800 ℃, the total plastic strain reaches 0.001 4. Plastic flow has a significant effect on the reduction of thermal stress concentration. 展开更多
关键词 functionally graded cemented carbides finite element method constraint factors elastoplastic response
下载PDF
Influence of the M and M’Metals on the Carbides Population in As-Cast M’-based Alloys Designed to be MC-Strengthened
7
作者 Patrice Berthod 《Journal of Metallic Material Research》 2019年第1期10-18,共9页
High temperature applications such as turbine blades for aeronautics or molten glass-shaping tools require the use of refractory metallic materials.Among the later ones,cast superalloys based on some transition metals... High temperature applications such as turbine blades for aeronautics or molten glass-shaping tools require the use of refractory metallic materials.Among the later ones,cast superalloys based on some transition metals and reinforced by MC carbides stay in good place and their metallurgy merits to be well known.This work consists in a general exploration of the as-cast microstructures which can be obtained after solidification and solid state cooling down to ambient temperature for a wide series of alloys for which the base element and the MC-former element both vary.For fixed contents in chromium and carbon contents,the compositions of a total of nineteen alloys were considered.These alloys are based on Ni,Co,Fe or Nb and the M content was each time chosen to favor the appearance of TiC,TaC,NbC,HfC or ZrC,as single carbide in a given alloy.After elaboration,metallographic samples were observed by electron microscopy to investigate the obtained microstructures.The obtained results show first that the MC carbides were in many cases successfully obtained at the expense of other possible carbides(for all Co-based alloys for example)but there are also several exceptions(notably for some Nibased alloys).Second,the obtained monocarbides have a eutectic origin and they are script-liked shaped.However they are here too some exceptions,as the rare HfC obtained in a Nb-base).In general,the results obtained in this work show that the principle of dendritic matrix combined with MC carbides with a script-like morphology is not necessarily obtained:the nature of the{base element,MC-former element}combination governs the microstructure of the alloy in its as-cast state for these particular compositions in chromium and carbon.In some cases other carbides may appear and the microstructures may be even of another type. 展开更多
关键词 Cast REFRACTORY ALLOYS MC carbides AS-CAST microstructures Base element monocarbides-former elements
下载PDF
Microstructure and formation process of Ni-pool defect in WC-8Ni cemented carbides 被引量:10
8
作者 时凯华 周科朝 +2 位作者 李志友 张斗 昝秀颀 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期873-878,共6页
The morphologies and formation process of Ni-pool defects in WC?8Ni cemented carbides were studied. The SEM images show that Ni-pool generally has two kinds of morphologies: “island” in isolation and “ring” around... The morphologies and formation process of Ni-pool defects in WC?8Ni cemented carbides were studied. The SEM images show that Ni-pool generally has two kinds of morphologies: “island” in isolation and “ring” around a new phase. In the obtained samples with “ring-like Ni-pool”, WC, Ni and Ni2W4C (η phase) phases were detected in XRD patterns. Combined with SEM, EDX and XRD results, it is found that the phase in the center of the “ring-like Ni-pool” is Ni2W4C (η phase) and the main chemical components of Ni-pool are Ni, W and C. In addition, the relationships among large size Ni (agglomerated) particles, volatile impurities, pores and carbon content vs forming process of the Ni-pool defects for WC?8Ni cemented carbides are also presented and discussed. 展开更多
关键词 cemented carbide WC-Ni alloy MICROSTRUCTURE FORMATION DEFECT
下载PDF
Effects of cubic carbides and La additions on WC grain morphology,hardness and toughness of WC-Co alloys 被引量:9
9
作者 张立 陈述 +3 位作者 程鑫 吴厚平 马鋆 熊湘君 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1680-1685,共6页
Effects of Cr3C2,VC and La2O3 additions on the WC grain morphology,hardness and toughness of WC-10Co alloys were investigated.To intensify the grain growth driving force,nano W and nano C,instead of the conventionally... Effects of Cr3C2,VC and La2O3 additions on the WC grain morphology,hardness and toughness of WC-10Co alloys were investigated.To intensify the grain growth driving force,nano W and nano C,instead of the conventionally used WC,were used as the starting materials.To obtain a three-dimensional WC grain morphology,the natural sinter skins of the alloys were observed directly by scanning electron microscopy.It is shown that the additions have a strong ability in regulating the WC grain morphological and grain size distribution characteristics and the combinations of hardness and toughness.Due to the formation of regular and homogeneous triangular platelet WC grains,WC-10Co-0.6Cr3C2-0.06La2O3 alloy shows an excellent combination of hardness and toughness.The morphological regulation mechanism,the relationship between the WC grain morphology and the properties were discussed. 展开更多
关键词 cemented carbide rare earth grain growth platelet WC grain hardness TOUGHNESS
下载PDF
Effects of deep cryogenic treatment on microstructure and properties of WC-11Co cemented carbides with various carbon contents 被引量:9
10
作者 谢晨辉 黄继武 +1 位作者 唐云锋 谷立宁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期3023-3028,共6页
The effects of deep cryogenic treatment on the microstructure and properties of WC-11 Co cemented carbides with various carbon contents were investigated.The results show that after deep cryogenic treatment,WC grains ... The effects of deep cryogenic treatment on the microstructure and properties of WC-11 Co cemented carbides with various carbon contents were investigated.The results show that after deep cryogenic treatment,WC grains are refined into triangular prism with sound edges via the process of spheroidization,but WC grain size has no evident change compared with that of untreated alloys.The phase transformation of Co phase from α-Co(FCC) to ε-Co(HCP) is observed in the cryogenically treated alloys,which is attributed to the decrease of W solubility in the binder(Co).Deep cryogenic treatment enhances the hardness and bending strength of the alloys,while it has no significant effects on the density and cobalt magnetic performance. 展开更多
关键词 WC-Co cemented carbide deep cryogenic treatment phase transformation MICROSTRUCTURE PROPERTIES
下载PDF
Properties and microstructure of VC/Cr_3C_2-doped WC/Co cemented carbides 被引量:8
11
作者 LEI Yiwen SUN Jing +2 位作者 DU Xiwen ZHAI Qi HU Shengliang 《Rare Metals》 SCIE EI CAS CSCD 2007年第6期584-590,共7页
This paper deals with the effects of codoped VC/Cr3C2 and sintering temperature on the magnetic and mechanical properties of ultra-fine grained WC-12%Co alloys. Results show that the synergistic action of doped VC/Cr3... This paper deals with the effects of codoped VC/Cr3C2 and sintering temperature on the magnetic and mechanical properties of ultra-fine grained WC-12%Co alloys. Results show that the synergistic action of doped VC/Cr3C2 in optimal proportion enhances both the hardness and transverse rupture strength (TRS) of the alloys, with more homogeneous microstructtLre. When the alloy is sintered at 1430℃ and with 0.5% Cr3C2/0.2% VC, the TRS reaches 3786 MPa, the hardness is 91.7 HRA and the grain size smaller than 0.6 μm. The numerical analyses on grain growth during the sintering process show that both VC precipitating on the WC grain boundary and Cr3C2 dissolving in the Co phase decrease the solid/liquid interfacial energy γ, the process of dissolution and reprecipitation is greatly retarded and the coarsening of WC grains is inhibited. 展开更多
关键词 grain growth inhibitor ultra-fine grain cemented carbides MICROSTRUCTURE transverse rupture strength (TRS)
下载PDF
Growth kinetics of cubic carbide free layers in graded cemented carbides 被引量:6
12
作者 Liu-yong Shi Yi-min Liu +2 位作者 Ji-hua Huang Shou-quan Zhang Xing-ke Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第1期64-71,共8页
In order to reveal the formation mechanism of cubic carbide free layers (CCFL), graded cemented carbides with CCFL in the surface zone were fabricated by a one-step sintering procedure in vacuum, and the analysis on... In order to reveal the formation mechanism of cubic carbide free layers (CCFL), graded cemented carbides with CCFL in the surface zone were fabricated by a one-step sintering procedure in vacuum, and the analysis on microstructure and element distribution were performed by scanning electron microscopy (SEM) and electron probe micro-analyzer (EPMA), respectively. A new physical model and ki- netic equation were established based on experimental results. Being different f^om previous models, this model suggests that nitrogen diffu- sion outward is only considered as an induction factor, and the diffusion of titanium through liquid phase plays a dominative role. The driving force of diffusion is expressed as the differential value between nitrogen partial pressure and nitrogen equilibrium pressure essentially. Simulation results by the kinetic equation are in good agreement with experimental values, and the effect of process parameters on the growth kinetics of CCFL can also be explained reasonably by the current model. 展开更多
关键词 graded materials cemented carbides DIFFUSION KINETICS
下载PDF
Deposition of tungsten-titanium carbides on surface of diamond by reactive PVD 被引量:5
13
作者 胡国荣 杨建红 +3 位作者 刘业翔 杨凯华 汤凤林 金继红 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第4期838-841,共4页
The coatings of W-Ti carbides on the surface of diamond was obtained by using physical vapor deposition (PVD), during which WO3 powders pre-treated with hydrofluoric acid were reduced by titanium hydride in vacuum at ... The coatings of W-Ti carbides on the surface of diamond was obtained by using physical vapor deposition (PVD), during which WO3 powders pre-treated with hydrofluoric acid were reduced by titanium hydride in vacuum at 850 ℃. The resistance of diamond to corrosion at high-temperature was investigated. The formation of W-Ti carbides on the surface of diamond was verified by X-ray diffraction analysis, the interface state between diamond and matrix in metaLbase diamond composite was observed by scanning electron microscope. The results showed that the carbide coating is easy to be formed at low deposition temperature on the surface of diamond, while the resistance of diamond to corrosion at highutemperature and the strength of bonding between diarnond and metal matrix are effectively improved. 展开更多
关键词 DIAMOND PHYSICAL vapor DEPOSITION (PVD) TUNGSTEN carbides TUNGSTEN
下载PDF
β→α Transformation of γ-Phase in Sintered WC-Co Cemented Carbides 被引量:5
14
作者 Shourong LIU (Tianjin Institute of Hard Alloy Tianjin 300222, China)Yi LIU (Shandong University Jinan 250100, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第5期398-400,共3页
Varying the morphology and the structure of γ-phase (Co-base Co-W-C solid solution) by means of altering the cooling rate and the preparing method of liquid sintered WC-Co cemented carbides samples, the mechanism of ... Varying the morphology and the structure of γ-phase (Co-base Co-W-C solid solution) by means of altering the cooling rate and the preparing method of liquid sintered WC-Co cemented carbides samples, the mechanism of fcc→hcp transformation of γ-phase in WC-Co alloy has been explored. The results show that, the cooling rate is an important affecting factor on fcc→hcp transformation of γ-phase and the fcc→hcp transformation is mainly a diffusive type when cooling WC-Co samples above room temperature 展开更多
关键词 WC CO Phase in Sintered WC-Co Cemented carbides Transformation of
下载PDF
Preparation and properties of Ni-coated WC powder and highly impact resistant and corrosion resistant WC-Ni cemented carbides 被引量:5
15
作者 Fan-lu MIN Song-bai YU +4 位作者 Sheng WANG Zhan-hu YAO Jacques Guillaume NOUDEM Si-jin LIU Jian-feng ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第6期1935-1947,共13页
WC powders were uniformly coated by Ni nanoparticles through a combined chemical co-precipitation and subsequent high temperature hydrogen reduction strategy(abbreviated as CM-WCN),and then were consolidated by vacuum... WC powders were uniformly coated by Ni nanoparticles through a combined chemical co-precipitation and subsequent high temperature hydrogen reduction strategy(abbreviated as CM-WCN),and then were consolidated by vacuum sintering at 1450°C for 1 h to obtain WC−Ni cemented carbides.The microstructure and properties of the as-consolidated CM-WCN were investigated.The average grain size of WC in the consolidated CM-WCN was calculated to be in the range of 3.0−3.8μm and only few pores were observed.A relative density of 99.6%,hardness of HRA 86.5 and bending strength of 1860 MPa were obtained for the CM-WCN−10wt.%Ni,and the highest impact toughness of 6.17 J/cm^(2 )was obtained for the CM-WCN−12wt.%Ni,surpassing those of the hand mixed WC−Ni(HM-WCN)cemented carbides examined in this study and the other similar materials in the literature.CM-WCN cemented carbides possess excellent mechanical properties,due to their highly uniform structure and low porosity that could be ascribed to the intergranular-dominated fracture mode accompanied by a large number of plastic deformation tears of the bonding phase.In addition,the corrosion resistance of CM-WCN was superior to that of HM-WCN at the Ni content of 6−12 wt.%. 展开更多
关键词 WC−Ni cemented carbides chemical co-precipitation method high temperature hydrogen reduction strategy Ni content microstructure impact toughness corrosion resistance
下载PDF
Change in relative density of WC-Co cemented carbides in spark plasma sintering process 被引量:4
16
作者 SUN Lan LIN Chenguang +2 位作者 JIA Chengchang JIA Xian XIAN Mina 《Rare Metals》 SCIE EI CAS CSCD 2008年第1期74-77,共4页
The relative density of WC-Co cemented carbides during spark plasma sintering(SPS) was analyzed.Based on the change in displacement of the ram in the SPS system,the relative densities in the sintering process can be... The relative density of WC-Co cemented carbides during spark plasma sintering(SPS) was analyzed.Based on the change in displacement of the ram in the SPS system,the relative densities in the sintering process can be achieved at different temperatures.The results indicated that densification of the samples started at near 900°C,the density rapidly reached its maximum at the increasing temperature stage,in which the temperature was lower than the sintering temperature of 1200°C,and most of the densification took place in the stage.Besides,the theoretical values were consistent with the experimental results. 展开更多
关键词 spark plasma sintering relative density WC-CO cemented carbides
下载PDF
Recent Progress in Emerging Two‑Dimensional Transition Metal Carbides 被引量:4
17
作者 Tianchen Qin Zegao Wang +3 位作者 Yuqing Wang Flemming Besenbacher Michal Otyepka Mingdong Dong 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第11期375-408,共34页
As a new member in two-dimensional materials family,transition metal carbides(TMCs)have many excellent properties,such as chemical stability,in-plane anisotropy,high conductivity and flexibility,and remarkable energy ... As a new member in two-dimensional materials family,transition metal carbides(TMCs)have many excellent properties,such as chemical stability,in-plane anisotropy,high conductivity and flexibility,and remarkable energy conversation efficiency,which predispose them for promising applications as transparent electrode,flexible electronics,broadband photodetectors and battery electrodes.However,up to now,their device applications are in the early stage,especially because their controllable synthesis is still a great challenge.This review systematically summarized the state-of-the-art research in this rapidly developing field with particular focus on structure,property,synthesis and applicability of TMCs.Finally,the current challenges and future perspectives are outlined for the application of 2D TMCs. 展开更多
关键词 Two-dimensional transition metal carbides Phase diagram SUPERCONDUCTIVITY Energy conversation and storage Largescale synthesis
下载PDF
Effect of deep cryogenic treatment on the formation of nano-sized carbides and the wear behavior of D2 tool steel 被引量:3
18
作者 Kamran Amini Amin Akhbarizadeh Sirus Javadpour 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第9期795-799,共5页
The effect of deep cryogenic treatment on the microstructure, hardness, and wear behavior of D2 tool steel was studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffracti... The effect of deep cryogenic treatment on the microstructure, hardness, and wear behavior of D2 tool steel was studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), hardness test, pin-on-disk wear test, and the reciprocating pin-on-fiat wear test. The results show that deep cryogenic treatment eliminates retained austenite, makes a better carbide distribution, and increases the carbide content. Furthermore, some new nano-sized carbides form during the deep cryogenic treatment, thereby increasing the hardness and improving the wear behavior of the samples. 展开更多
关键词 cryogenic treatment tool steel nano-sized carbides wear resistance HARDNESS AUSTENITE
下载PDF
Precipitation and decomposition behaviors of carbides in AISI M2 high-speed steel with nitrogen and mischmetal 被引量:4
19
作者 LIU Bao-long Lü Zhi-qing +2 位作者 FENG Wei-wei REN Ting-zhi FU Wan-tang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期782-788,共7页
The behaviors of the precipitation and decomposition of carbides in AISI M2 high-speed steel modified by nitrogen and mischmetal were investigated using DSC, XRD, SEM and TEM. The as-cast microstructure of the experim... The behaviors of the precipitation and decomposition of carbides in AISI M2 high-speed steel modified by nitrogen and mischmetal were investigated using DSC, XRD, SEM and TEM. The as-cast microstructure of the experimental steel consists of dendrites of iron matrix, networks of eutectic carbides and secondary carbides. The average distance between networks is about 34 μm. The carbides mainly include M_2C, M(C,N) and M_6C, and their relative contents are 58.5%, 30.3% and 11.2%, respectively. The average spacing between the M_2C fibers is 1.5 μm. The decomposition of M_2C occurs from 897.2 to 1221.5 ℃(heating rate of 200 ℃/h). Some precipitated carbide particles occur in the M_2C matrix after holding for 15 min at 1100 ℃. With increasing holding time, the carbide fibers neck down more and more obviously until they are broken down. The spectral peaks of M_2C almost disappear after holding for 60 min. The spectral peaks of M_6C gradually strengthen with the holding time, and the relative content of M_6C increases to 79.8% after holding for 60 min. After holding for 180 min, the carbide fibers disappear, and the decomposition products consist of fine carbide particles(about 300 nm) and short rod-like carbides(about 3.5 μm). 展开更多
关键词 high-speed steel metastable carbides decomposition phase transformation refinement
下载PDF
Study on primary carbides precipitation in H13 tool steel regarding cooling rate during solidification 被引量:4
20
作者 Guang-di Zhao Xi-min Zang +2 位作者 Wan-ming Li Zhuo Zhao De-jun Li 《China Foundry》 SCIE 2020年第3期235-244,共10页
This study aims to investigate the primary carbides precipitation in H13 steel solidified at relatively high cooling rates,ranging from 300 to 6,000℃·min^-1,based on in situ observations with a high temperature ... This study aims to investigate the primary carbides precipitation in H13 steel solidified at relatively high cooling rates,ranging from 300 to 6,000℃·min^-1,based on in situ observations with a high temperature confocal laser scanning microscope.In the cooling rate range investigated,the solidification microstructure becomes more refined as cooling rate increases and the relationship between the secondary dendrite arm spacing(SDAS),λ2,and cooling rate,.T,can be expressed asλ2=128.45.T-0.124.Regardless of cooling rates,two kinds of primary carbides,i.e.,the Mo-Cr-rich and V-rich carbides,are precipitated along the interdendritic region and most of them are the Mo-Cr-rich carbides.The morphology of Mo-Cr-rich carbide is not obviously influenced by the cooling rate,but that of V-rich carbide is obviously affected.The increasing cooling rate markedly refines the primary carbides and reduces their volume fractions,but their precipitations cannot be inhibited even when the cooling rate is increased to 6,000℃·min^-1.Besides,the segregation ratios(SRs)of the carbides forming elements are not obviously affected by the cooling rate.However,compared with the conventionally cast ingot,the SDAS and primary carbides in the steel solidified at the investigated cooling rates are much finer,morphologies of the carbides have changed significantly,and SRs of the carbides forming elements are markedly greater.The variation of primary carbide characteristics with cooling rate is mainly due to the change in SDAS. 展开更多
关键词 H13 steel cooling rate SOLIDIFICATION primary carbides
下载PDF
上一页 1 2 70 下一页 到第
使用帮助 返回顶部