检索结果-南通市图书馆

Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1657-1665页

作者： Pengfei Gao Weijian Chen Feng Li Beijia Ning Zhengzhi Zhao Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Beijing 100083China

The relationship between microstructure morphology and mechanical properties of the low-carbon steel(Fe-0.20 C-2.59 Mn-2.13 Si)treated by diff erent intercritical annealed quenching and partitioning(Q&P)processes was investigated through interrupted tensile tests plus quasi-situ electron backscatter diff raction measurements.Results show that size and distribution of retained austenite(RA)directly aff ect the sequence of deformation induced martensitic transformation.As strain increases,the equiaxed RA grains wrapped by ferrite transform fi rst,followed by the equiaxed and fi lm-like RA grains adjacent to martensite.Compared with traditional intercritical annealed Q&P steel with equiaxed structure,the steel with quenching pretreatment contains uniform lamellar structure and the relatively fi lm-like type of RA,leading to the higher yield strength,tensile strength,and elongation,as well as the steady increase in dislocation density upon straining.

关键词： Steel Quenching and partitioning austenite Martensitic transformation Electron backscatter diffraction(EBSD) Tensile test

Texture development and properties of Ti-IF steels produced by different hot-rolling processes

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2019年第3期26卷 310-320页

作者： Lei-lei Hao Lang Li Chen-yang Qiu Jian-gong Wang Xun Zhou Yong-lin Kang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Shougang Jingtang United Iron and Steel Co. Ltd.Tangshan 063200HebeiChina

Texture is a pivotal factor for the deep drawability of interstitial free steel (IF steel). The evolution of microstructure and recrystallization texture of Ti-IF steel through the processing of hot rolling, cold rolling and annealing have been studied. The mechanical properties including strain hardening index n and plastic strain ratio r are also measured. For comparison, ferrite rolling and austenite rolling are both studied. The results show that the intensity of γ-fiber after ferrite rolling is higher than that after austenite rolling. The great balance between the {111}〈110〉 and {111}〈112〉 leads to low △r value after annealing. The size of precipitates in ferrite rolled sample is generally larger than that in austenite rolled sample. Compared to austenite rolled sample, the ferrite rolled and annealed one has better formability and its r value reaches 2.36. Different from laboratory production, the test steels were acquired from industrial trial, and all the result can be used in industrial production directly.

关键词： Ti-IF steel Ferrite rolling austenite rolling Microstructure Texture

Ultra-fine ferrite grains obtained in the TSDR process

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of University of Science and Technology Beijing 2008年第5期15卷 568-573页

作者： Ling Zhang Wangyue Yang Chunxia Xue Zuqing Sun School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China The State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

By careful design of rolling schedule,ultra-fine （～2μm） ferrite grains in a low carbon high niobium （0.09wt%Nb） microalloying steel with average austenite grain sizes above 800 μm can be achieved in the simulated thin slab direct rolling process. The 5-pass deformation was divided into two stages： the refinement of austenite through complete recrystallization and the refinement of ferrite through dynamic strain-induced transformation. The effects of Nb in solution and strain-induced NbCN precipitates on the ferrite transformation were also extensively discussed.

关键词： ultra-fine ferrite niobium precipitation austenite recrystallization thin slab direct rolling

Effect of intercritical deformation on tensile performance of a low-carbon Si-Mn steel processed by quenching and bainitic partitioning

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2020年第2期27卷 208-216页

作者： Ya-qiang Tian Zhong-qian Cao Wang Li Hong-bo Pan Xiao-ping Zheng Jin-ying Song Ying-li Wei Lian-sheng Chen Key Laboratory of the Ministry of Education for Modern Metallurgy Technology North China University of Science and TechnologyTangshan 063210HebeiChina Key Laboratory of Metallurgical Emission Reduction and Resources Recycling of Ministry of Education Anhui University of TechnologyMa'anshan 243002AnhuiChina

The effect of intercritical deformation on retained austenite and tensile performance of a low-carbon Si-Mn steel in modified quenching and bainitic partitioning processes was evaluated.The results showed that the intercritical deformation can play a positive role in stabilizing and refining the retained austenite,and possessed promising potential in balancing tensile strength and ductility of multiphase high-strength steels.The experimental low-carbon Si-Mn steel exhibited multiphase configuration comprising polygonal ferrite,granular bainite and granular structure after two different modified quenching and bainitic partitioning processes,and the bainitic ferrite laths got refined by intercritical deformation.The volume fraction of retained austenite in film-like and blocky morphology was increased from 11.5%to 13.9%due to applied intercritical deformation,and the larger amount of retained austenite provided the sufficient transformation-induced plasticity effect and resulted in enhanced work hardening degree;in response,enhanced ultimate tensile strength 1260 MPa and fracture elongation 22.1%were obtained,leading to increased product of strength and elongation in value of 27.7 GPa% compared to 20.8 GPa% of undeformed structure.

关键词： Bainitic steel Intercritical deformation Retained austenite Instantaneous work hardening index Transformation-induced plasticity effect

Effect of Ti on microstructure and strengthening behavior in press hardening steels

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Central South University 2017年第10期24卷 2215-2221页

作者：闻玉辉朱国明戴思雨康永林 School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials(University of Science and Technology Beijing) Beijing 100083China

Effect of Ti addition on the microstructure and strengthening behavior in press hardening steels(PHS)was analyzed by optical metallography(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray diffraction(XRD).The results show that the microstructure of PHS is martensite,and two sizes of particles disperse in the martensite matrix during the forming and quenching process.The size of the bigger particles is between 100 and 200 nm,and the small particles are nanometer-sized.The quantity of the particles has a positive relation with the Ti content.More importantly,the microstructure and strengthening mechanism are affected by the precipitating behavior of the particles.Besides the prior austenite grain,martensite packet,block and lath are refined by Ti addition.The steels are strengthened by the fine grains,martensite substructure and precipitates.The uniformly distributed dislocation in the martensite lath,the density of which is between 3.0?10^(14) cm^(–2) and 5.0?10^(14) cm^(–2),strengthens the steels through associating with fine carbide particles.

关键词： martensite particles prior austenite grain martensite lath press hardening steel

Crystallographic Analysis of Martensite in 0.2C-2.0Mn-1.5Si-0.6Cr Steel using EBSD

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2011年第10期27卷 920-930页

作者： Pasi P.Suikkanen Cyril Cayron Anthony J.DeArdo L.Pentti Karjalainen Department of Mechanical Engineering University of OuluBox 420090014 University of Oulu CEA LITEN17 rues des Martys38054GrenobleFrance Department of Mechanical Engineering and Materials Science University of Pittsburgh

The crystallography of martensite formed in 0.2C-2.0Mn-1,5Si-0.6Cr steel was studied using the electron backscattered diffraction （EBSD） technique. The results showed that the observed orientation relationship （OR） was closer to that of Nishiyama-Wassermann （N-W） than Kurdjumov-Sachs. The martensite consisted of parallel laths forming morphological packets. Typically, there were three different lath orientations in a morphological packet consisting of three specific N-W OR variants sharing the same {111} austenite plane. A packet of martensite laths with a common {111} austenite plane was termed a crystallographic packet. Generally, the crystallographic packet size corresponded to the morphological packet size, but occasionally the morphological packet was found to consist of two or more crystallographic packets. Therefore, the crystallographic packet size appeared to be finer than the morphological packet size. The relative orientation between the variants in crystallographic packets was found to be near 60°〈110〉, which explains the strong peak observed near 60° in the grain boundary misorientation distribution. Martensite also contained a high fraction of boundaries with a misorientation in the range 2.5-8°. Typically these boundaries were found to be located inside the martensite laths forming sub-laths.

关键词： Martensite austenite Nishiyama-Wassermann orientation relationship EBSD Crystallography Packet

Effect of tempering temperature on the microstructure and properties of ultrahigh-strength stainless steel

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2019年第7期35卷 1240-1249页

作者： Yangpeng Zhang Dongping Zhan Xiwei Qi Zhouhua Jiang School of Metallurgy Northeastern UniversityShenyang110819China School of Materials Science and Engineering Northeastern UniversityShenyang110819China

The microstructure, precipitation and mechanical properties of Ferrium S53 steel, a secondary hardening ultrahigh-strength stainless steel with 10% Cr developed by QuesTek Innovations LLC, upon tem pering were studied by scanning electron microscopy (SEM), transm ission electron microscopy (TEM), X-ray diffraction (XRD), and tensile and impact tests. Based on these results, the influence of the tem pering temperature on the microstructure and properties was discussed. The results show th at decom position occurred when the retained austenite was tem pered above 440 ℃ and that the hardening peak at 482 ℃ was caused by the joint strengthening of the precipitates and martensite transformation. Due to the high Cr content, the trigonal M7C3 carbide precipitated w hen the steel was tem pered at 400 ℃, and M7C3 and M2C (5 -10 nm in size) coexisted w hen it was tem pered at 482 ℃. When the steel was tem pered at 630 ℃, M2C and M23C6 carbides precipitated, and the sizes w ere greater than 50 nm and 500 nm, respectively, but no M7C3 carbide formed. When the tempering tem perature was above 540 ℃, austenitization and large-size precipitates w ere the main factors affecting the strength and toughness.

关键词： Age hardening austenite Precipitation Tempering Strengthening mechanism M7C3

Constituent phases of the passive film formed on 2205 stainless steel by dynamic electrochemical impedance spectroscopy

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 42-47页

作者： Xue-qun Cheng Cheng-tao Li Chao-fang Dong Xiao-gang Li Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China Key Laboratory of the Ministry of Education of China for Corrosion and Protection Beijing 100083 China

The passive film formed on 2205 duplex stainless steel（DSS） in 0.5 M NaHCO3＋0.5 M NaCl aqueous solution was characterized by electrochemical measurements,including potentiodynamic anodic polarization and dynamic electrochemical impedance spectroscopy（DEIS）.The results demonstrate that there is a great difference between the passive film evolutions of ferrite and austenite.The impedance values of ferrite are higher than those of austenite.The impedance peaks of ferritic and austenitic phases correspond to the potential of 0.15 and 0.25 V in the low potential range and correspond to 0.8 and 0.75 V in the high potential range.The evolutions of the capacitance of both phases are reverse compared to the evolutions of impedance.The thickness variations obtained from capacitance agree well with those of impedance analysis.The results can be used to explain why pitting corrosion occurs more easily in austenite phase than in ferrite phase.

关键词： stainless steel electrochemical impedance spectroscopy ferrite austenite passivation films

Crystallographic Analysis of Isothermally Transformed Bainite in 0.2C-2.0Mn-1.5Si-0.6Cr Steel Using EBSD

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2013年第4期29卷 359-366页

作者： Pasi P.Suikkanen Cyril Cayron Anthony J.DeArdo L.Pentti Karjalainen Ruukki Metals Oy Rautaruukintie 155P.O.Box 93FI-92101 RaaheFinland Department of Mechanical Engineering University of OuluP.O.Box 420090014 University of OuluFinland Ruukki Metals Oy Rautaruukintie 155P.O.Box 93FI-92101 RaaheFinland. CEA LITEN17 rues des Martys38054 GrenobleFrance Department of Mechanical Engineering and Materials Science University of Pittsburgh848 Benedum HallPittsburghPA 15261-2285USA

The crystallography of bainite, transformed isothermally at 450 ℃ in 0.2C-2.0Mn-1.5Si-0.6Cr steel, was investigated by electron backscatter diffraction （EBSD） analysis. The orientation relationship （OR） was found to be closer to Nishiyama-Wassermann （N-W） than Kurdjumov-Sachs orientation relationship. Bainite microstructure consisted of parallel laths forming a morphological packet structure. Typically, there were three different lath orientations in a morphological packet. These orientations were dictated by a three specific N-W OR variants sharing the same {111} austenite plane. A packet of bainite laths with common {111} austenite plane was termed as crystallographic packet. Generally, the crystallographic packet size corresponded to the morphological packet size. Locally, crystallographic packets with only two dominant orientations were observed. This indicates strong local variant selection during isothermal bainite transformation. The relative orientation between the variants in crystallographic packets was found to be near 60°/〈110〉. This appears to explain the strong peak observed in the grain boundary misorientation distribution near 60°. Bainite also contained pronounced fraction of boundaries with their misorientation in the range of 2.5°-8° with quite widely dispersed rotation angles. Spatially these boundaries were found to locate inside the bainite laths, forming lath-like sub-grains.

关键词： Bainite austenite Nishiyama-Wassermann orientation relationship Electron backscatter diffraction OEBSD） Crystallography Packet

Correlation between microstructure and impact toughness of weld heat-affected zone in 5 wt.% manganese steels

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2019年第7期26卷 761-770页

作者： Jun-hui Li Hong-hong Wang Qiang Luo Li Li Chao Sun R.D.K. Misra The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan 430081 Hubei China Research Institute of Nanjing Iron and Steel Co. Ltd. Nanjing 210035 Jiangsu China Laboratory for Excellence in Advanced Steel Research Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso El Paso TX 7996& USA

The microstructure in welding heat-affected zones of 5 wt.% manganese steels was studied, and its effect on impact toughness was analyzed. The simulated coarse-grained heat-affected zone (CGHAZ) had the lowest impact toughness of ~39 J at — 40℃ because of coarse-grained structure and least volume fraction of retained austenite (RA) of 1.2 vol.%. The impact toughness of simulated intercritical heat-affected zone (ICHAZ) and fine-grained heat-affected zone (FGHAZ) were ~165 and ~45 J, respectively, at — 40℃. The effective grain size of simulated FGHAZ was smaller than that of the simulated ICHAZ. Furthermore, microstructural investigation revealed that the simulated FGHAZ and ICHAZ had similarity in volume fraction and stability of RA. However, tempered martensite was present in ICHAZ and absent in FGHAZ. It is proposed that the presence of tempered martensite contributed to good impact toughness in simulated ICHAZ.

关键词： 5 wt.% manganese steel Welding heat-affected zone Retained austenite Tempered martensite Impact toughness