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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 536-546页

作者： Chen-yang Qiu Lang Li Lei-lei Hao 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 063200China 不详

In this report,the microstructure,mechanical properties,and textures of warm rolled interstitial-free steel annealed at four different temperatures(730,760,790,and 820°C)were *** overall structural features of specimens were investigated by optical microscopy,and the textures were measured by X-ray diffraction(XRD).Nano-sized precipitates were then observed by a transmission electron microscope(TEM)on carbon extraction *** to the results,with increased annealing temperatures,the ferrite grains grew;in addition,the sizes of Ti_4C_2S_2 and Ti C precipitates also ***,the sizes of Ti N and Ti S precipitates slightly *** the annealing temperature increased from 730 to 820°C,the yield strength(YS)and the ultimate tensile strength(UTS)showed a decreasing ***,elongation and the strain harden exponent(n value)increased to 49.6%and 0.34,*** comparing textures annealed at different temperatures,the intensity of{111}texture annealed at 820°C was the largest,while the difference between the intensity of{111}and{111}was the smallest when the annealing temperature was 820°***,the plastic strain ratio(r value)annealed at 820°C was the highest.

关键词： interstitial-free steel warm rolling texture mechanical properties microstructure

Establishment of Multiple Locus Variable-number Tandem Repeat Analysis Assay for Genotyping of Borrelia burgdorferi sensu lato Detected in China

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Biomedical and Environmental Sciences 2014年第9期27卷 665-675页

作者： ZHOU Xin HOU Xue Xia GENG Zhen ZHAO Rui WAN kang lin HAO Qin National Institute for Communicable Disease Control and Prevention State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Clinical Laboratory Center Shanxi provincial children and womenHospital

Objective Human Lyme Borreliosis （LB）, which is caused by Borrefia burgdorferi sensu lato （B. burgdorferi）, has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multiple locus variable-number tandem repeat （VNTR） analysis （MLVA） assay for the genotyping of Borrelia burgdorJ：eri strains detected in China. Methods B. garinii PBi complete 904.246 kb chromosome and two plasmids （cp26 and Ip54） were screened by using Tandem Repeats Finder program for getting potential VNTR loci, the potential VNTR loci were analyzed and identified with PCR and the VNTR loci data were analyzed and MLVA clustering tree were constrcted by using the categorical coefficient and the unweighted pair-group method with arithmetic means （UPGMA）. Results We identified 5 new VNTR loci through analyzing 47 potential VNTR loci. We used the MLVA protocol to analyse 101 B. burgdorferi strains detected in China and finally identified 51 unique genotypes in 4 major clusters including B. burgdorferi sensu stricto （B.b.s.s）, B. garinii, B. a[zelii, and B. valaisiana, consistent with the current MLSA phylogeny studies. The allele numbers of VNTR-1, VNTR-2, VNTR-3, VNTR-4, and VNTR-5 were 7, 3, 9, 7, and 6. The Hunter-Gaston index （HGI） of five VNTR loci were 0.79, 0.22, 0.77, 0.71, and 0.67, respectively. The combined HGI of five VNTR loci was 0.96. Clustering of the strains of Xinjiang, Inner Mongolia and Heilongjiang was confirmed, and this situation was consistent with the close geographical distribution of those provinces. Conclusion The MLVA protocol esytablished in this study is easy and can show strains＇ phylogenetic relationships to distinguish the strains of Borrelia species. It is useful for further phylogenetic and epidemiological analyses of Borrelia strains.

关键词： Borrelia burgdoferi sensu lato MLVA VNTR MLSA Genotyping

Effect of Cooling Start Temperature on Microstructure and Mechanical Properties of X80 High Deformability Pipeline Steel

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Journal of Iron and Steel Research International 2011年第10期18卷 42-46,71页

作者： ZHENG Xiao-fei kang Yong-lin MENG De-liang AN Shou-yong XIA Dian-xiu School of Materials Science and Engineering State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China Jinan Iron and Steel Group Corp Jinan 250101 Shandong China

The effect of cooling （laminar cooling） start temperature on the phase constitution was analyzed by quanti- tative metallography. The martensite/austenite （M/A） island distribution was fixed by colour metallography. The strength and uniform elongation of the steels were tested with quasi-static tensile testing machine. The in-coordinate deformation of the soft and hard phases was analyzed using FEM. The results indicate that when the cooling start temperature is 690 ℃, the mechanical properties are the best, meeting the requirements of X80 high deformability pipeline steel.

关键词： high deformability pipeline steel cooling start temperature carbon diffusion in-coordinate deformationsM/A island

Microstructure and Properties of Mo Microalloyed Cold Rolled DP1000 Steels

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Journal of Iron and Steel Research International 2011年第5期18卷 52-58页

作者： HAN Qi-hang kang Yong-lin ZHAO Xian-meng Lu Chao GAO Lu-feng School of Materials Science and Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China

Two kinds of ultra-high strength cold rolled dual phase steels have been developed by designing C-Si-Mn-Cr and C-Si-Mn-Cr-Mo alloy systems. Tensile strength and elongation of both steels exceed 1100 MPa and 10%,respectively. The microstructures of both steels consist of massive martensite and ferrite. And the massive martensite of Mo-free steel disperses in the ferrite with volume fraction of 64%. However,the massive martensite of Mo-containing steel is connected or closed by small martensite islands each other,and martensite volume fraction is 69%. As to Mo-free steel,the yield strength,yield ratio,and work hardening exponent n are 548 MPa,0.49,and 0.26,respectively. As for Mo-containing one,the yield strength,yield ratio,and n value are 746 MPa,0.66,and 0.33,respectively. Besides,the ferrite of Mo-free steel is deformed at the initial stage of plastic deformation. However,for Mo-containing one,Mo solution strengthened ferrite and small overaged martensite islands are deformed preferentially at small strain,which causes the yield strength to reach approximately 200 MPa higher than that of Mo-free steel.

关键词： Mo dual phase steel microstructure property deformation mechanism

Precipitation Behavior and Its Strengthening Effect of X100 Pipeline Steel

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Journal of Iron and Steel Research International 2010年第11期17卷 73-78页

作者： NIU Tao kang Yong-lin GU Hong-wei YIN Yu-qun QIAO Ming-liang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China Nanjing Iron and Steel Co Ltd Nanjing 210035 Jiangsu China

Using TEM （transmisson electron microscopy）, electron diffraction, EDX （energy dispersive X-ray） analysis and physicochemical phase analysis, the morphology, crystal structure, size distribution and chemical composition of precipitates in the microstructure of high strength Nb-microalloyed Xl00 pipeline steel were investigated, and the strengthening effect of precipitation was quantitatively calculated with Ashhy-Orowan correction model. The precipitates obtained in X100 pipeline steel can be divided into two kinds：＂complex＂ and ＂single＂ particles by morphology. The EDX analysis of ＂single＂ precipitates reveals that the chemical composition matches well with particle dimensions, especially the Nb to Ti ratio regularly decreases with the increase of particle size. The yield strength increments in the way of precipitation strengthening of X100 pipeline steel reached about 52 MPa, suggesting that the precipitation strengthening is not the dominative strengthening mechanism for X100 pipeline steel.

关键词： X100 pipeline steel carbonitride precipitation behavior strengthening effect

3D Thermo-mechanical Coupled Simulation of Whole Rolling Process for 60kg/m Heavy Rail

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Journal of Iron and Steel Research International 2014年第12期21卷 1104-1110页

作者： Nuan-nuan PEI Guo-ming ZHU Bo LI Gong-ming TAO Yong-lin kang School of Materials Science and Engineering University of Science and Technology Beijing Pangang Group Panzhihua Steel & Vanadium Co. Ltd.

3D thermo-meehanical coupled simulation of whole rolling process for 60 kg/m heavy rail was accomplished by FEM method. The finite element model, physical parameters of U75V and parameter setting of simulation were introduced in detail. The whole rolling process of 60 kg/m heavy rail was divided into 27 time cells to simulate respectively, and the model rebuilding and temperature inheritance method in intermediate pass were proceeded. Then, based on simulation results, the workpiece deformation result, metal flow, stress and strain of 60 kg/m heavy rail for typical passes were obtained. The temperature variation curves of whole rolling process for section key points of 60 kg/m heavy rail were plotted, and the temperature falling law of whole rolling process for 60 kg/m heavy rail was studied. In addition, temperature distribution of 60 kg/m heavy rail after whole rolling process was analyzed, and the results showed that temperature was highest at center of rail head and lowest at fringe of rail base. Moreover, the simulation results and measured results of rolling force for 60 kg/m heavy rail were compared, and the regularity was in good agreement.

关键词： heavy rail thermo-mechanical coupled simulation metal flow stress strain temperature rolling force

Cloning and characterization of a gene encoding phage-related tail protein (PrTP) of endosymbiont Wolbachia

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Chinese Science Bulletin 2002年第17期47卷 1451-1456,1497页

作者： lin kang Lei Sun Hong Yu Weiguo Zhou Shouyuan Zhao Changben Li Fudan Univ Inst Genet State Key Lab Genet Engn Shanghai 200433 Peoples R China

Wolbachia is an obligatory, maternally inherited intracellular bacterium, known to infect a wide range of arthropods. It has been implicated in causing cytoplasmic incompatibility (CI), parthenogenesis, the feminization of genetic males and male-killing in different hosts. However, the molecular mechanisms by which this fastidious bacterium causes these reproductive abnormalities have not yet been determined. In this study, we report on the cloning and characterization of the gene encoding phage-related tail protein (PrTP) from Wolbachia in Drosophila melanogaster CantonS (wMelCS) and from Wolbachia in Drosophila melanogaster yw67c23 (wMel) by representational difference analysis (RDA) and ligation-mediated PCR (LM-PCR). The functionality of a bipartite nuclear localization signal sequence (NLS) of the gene was also successfully tested in Drosophila S2 cells. PrTP expression in various strains of Wolbachia was investigated. Our results suggest that PrTP may not induce CI directly. However, the

关键词： Wolbachia CI prtp NLS HGT.

Dynamic CCT Diagram of Automobile Beam Steel With High Strength Produced by FTSR Technology

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Journal of Iron and Steel Research International 2008年第2期15卷 60-64页

作者： WANG Xin kang Yong-lin YU Hao CHEN Li-bin KONG Qing-fu Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Center of Technology Tangshan Iron and Steel Group Company Tangshan 063016 Hebei China

The dynamic continuous cooling transformation（CCT）diagram and phase transformation rules of 510 MPa automobile beam steel,which is produced by a continuous casting of thin slab of FTSR technology in Tangshan Iron and Steel ***.,are researched by thermal simulation *** microstructure characteristics of the beam steel under different test conditions are studied by means of optical microscope and scanning electron *** test results show that the critical temperatures of phase transformation Ar3 and Ar1 will all decrease with the increase of the cooling *** the cooling rate is lower than 20 ℃·s-1,the ferrite and pearlite phase transformations are the main parts;when the cooling rate is higher than 20 ℃·s-1,the bainite phase ***,the microstructures of 510 MPa automobile beam steel produced by FTSR technology are also studied,and the results are basically in accordance with the CCT diagram gained from the test.

关键词： continuous cooling transformation automobile beam steel continuous thin slab casting microstructure characteristics

The Effect of Nb on Mechanical Properties of Quenching and Partitioning Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 306-309页

作者： ZHU Shuai,kang Yong-lin,REN kang-kang,WANG Chuan (School of Materials Science and Engineering.University of Science and Technology Beijing,Beijing 100083,China) Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

In order to study the effect of alloy elements on mechanical properties of quenching and partitioning steels,the Q and P heat treatments on different chemical composition steels were carried on in *** tensile test results indicated the strength of Nb+Ti-bearing steel was not increasing as expected,but lower than that of the Nb+Ti-free steel,and the elongation was raised to 26% from 9%.The Nb+Ti-bearing steel microstructures after tensile test were detected by TEM and found a certain amount of twins in the deformed microstructure while the deformed microstructure mainly was lath martensite in Nb+Ti-free steel,which means the addition of Nb and Ti elements could cause the twinning induced plasticity by inhibiting the phase transformation from austenite to *** on above analysis,adding trace Nb element could greatly increase the stacking fault energy of the retained austenite,which is beneficial to the formation of twins,and the formation of twins would lower the strength slightly and raise the elongation drastically.

关键词： quenching and partitioning twinning induced plasticity niobium stacking fault energy

Simulation and experiment of vortex transport properties in a Type Ⅱ superconductor with grain boundary

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Science China(Technological Sciences) 2015年第3期58卷 493-498页

作者： JIANG Lai XU WeiWei HUA Tao YU Mei AN DeYue CHEN Jian JIN BiaoBing kang lin WU PeiHeng Research Institute of Superconductor Electronics School of Electronic Science and Engineering Nanjing University

We firstly described a simulation model to investigate the influence of grain boundary(GB)on the vortex transport properties in YBCO *** is found that the size of inhomogeneous area caused by GB as well as the average velocity in transverse and longitudinal directions shows an angular dependence when the angle between the GB and the sample edge *** have also studied the impact of magnetic field intensity on dynamic behavior of vortex lattice and found that a lower vortex density makes it difficult for the vortex lattice to transfer from pinning state to flow *** the magnetic field is decreased beyond a critical value,sharp jumps and strong fluctuations were observed in the I-V ***,we conducted measurements on a thin film YBa2Cu3O7 with an individual artificial grain boundary to support the simulation process.

关键词： high-Tc superconductor grain boundary vortex dynamic