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排序方式: 共有6368条查询结果,搜索用时 15 毫秒
31.
Mechanical performance and texture characteristic of an IF steel containing Nb and Ti by double cold rolling 总被引:1,自引:0,他引:1
Ling-yun Wang) Peng Zhang ) Wei Li) Guang-jie Huang) ) College of Materials Science Engineering Chongqing University Chongqing China ) Technology Institute of Sichuan Chuanwei Group Co. Ltd. Weiyuan China 《北京科技大学学报(英文版)》2009,16(1):51-57
Single cold rolling and double cold rolling were applied to hot rolled strips with different reduction ratios. The evolutions of {100},{111} and Goss face texture during double rolling were investigated by comparing the orientation distribution function(ODF) of the double rolled sample with that of the single rolled one. The double cold rolling texture is characterized by a higher γ-texture and a lower α-texture,and the {111}<112> component is improved remarkably. Based on the TEM observation and mechanical... 相似文献
32.
Effects of welding wire composition and welding process on the weld metal toughness of submerged arc welded pipeline steel 总被引:2,自引:0,他引:2
De-liang Ren ) Fu-ren Xiao) Peng Tian) Xu Wang) Bo Liao) ) Key Lab of Metastable Materials Science & Technology College of Materials Science & Engineering Yanshan University Qinhuangdao China ) Department of Materials Science Engineering Shijiazhuang Railway Institute Shijiazhuang China ) Steel Pipe Works of North China Petroleum Qing County China 《北京科技大学学报(英文版)》2009,16(1):65-70
The effects of alloying elements in welding wires and submerged arc welding process on the microstructures and low-temperature impact toughness of weld metals have been investigated.The results indicate that the optimal contents of alloying elements in welding wires can improve the low-temperature impact toughness of weld metals because the proentectoid ferrite and bainite formations can be suppressed,and the fraction of acicular ferrite increases.However,the contents of alloying elements need to vary along with the welding heat input.With the increase in welding heat input,the contents of alloying elements in welding wires need to be increased accordingly.The microstructures mainly consisting of acicular ferrite can be obtained in weld metals after four-wire submerged arc welding using the wires with a low carbon content and appropriate contents of Mn,Mo,Ti-B,Cu,Ni,and RE,resulting in the high low-temperature impact toughness of weld metals. 相似文献
33.
Antibacterial and corrosive properties of copper implanted austenitic stainless steel 总被引:1,自引:0,他引:1
Juan Xiong) Bo-fan Xu) Hong-wei Ni) ) School of Physics Electronic Technology Hubei University Wuhan China ) School of Material Metallurgy Wuhan University of Science Technology Wuhan China 《北京科技大学学报(英文版)》2009,16(3):293-298
Copper ions were implanted into austenitic stainless steel (SS) by metal vapor vacuum arc with a energy of 100 keV and an ions dose range of (0.5-8.0)×1017 cm-2. The Cu-implanted SS was annealed in an Ar atmosphere furnace. Glancing X-ray diffrac-tion (GXRD), transmission electron microscopy (TEM) and Auger electron spectroscopy (AES) were used to reveal the phase compositions, microstructures, and concentration profiles of copper ions in the implanted layer. The results show that the antibacterial property... 相似文献
34.
Evolution of carbides and carbon content in matrix of an ultra-high carbon sintered steel during heat treatment process 总被引:2,自引:0,他引:2
Yuan-zhi Zhu ) Zhe Zhu) Zhi-min Yin) Zhi-dong Xiang) ) Key Laboratory of the Ministry of Education of China for Ferrous Metallurgy Resources Utilization Wuhan University of Science Technology Wuhan China ) School of Materials Metallurgy China ) School of Material Science & Engineering Central South University Changsha China 《北京科技大学学报(英文版)》2009,16(3):299-303
DTA, thermal expansion, XRD, and SEM were used to evaluate the effect of quenching temperature on the mechanical properties and microstructure of a novel sintered steel Fe-6Co-1Ni-5Cr-5Mo-1C. Lattice parameters and the mass fraction of carbon dissolved in the matrix of the steel quenched were investigated. It is discovered that the hardness of the steel increases with quench-ing temperature in the range of 840-900℃ and remains constant in the range of 900 to 1100℃. It decreases rapidly when the tem-perature is higher than 1100℃. The mass fraction of carbon dissolved in the matrix of the steel quenched at 840℃ is 0.38, but when the quenching temperature is increased to 1150℃, it increases to 0.98. The carbides formed during sintering are still present at grain boundaries and in the matrix of the steel quenched at low quenching temperatures, such as 840℃. When the quenching temperature is increased to 1150℃, most of the carbides at grain boundaries are dissolved with just a small amount of spherical M23C6 existing in the matrix of the quenched steel. 相似文献
35.
Hong Zhang) Xiao-gang Li) Cui-wei Du) Hui-bin Qi) ) School of Materials Science Engineering University of Science Technology Beijing Beijing China ) Institute of Welding Surface Technology Baoshan Iron & Steel Co. Ltd. Shanghai China 《北京科技大学学报(英文版)》2009,16(4):414-421
The corrosion behavior and mechanism of hot-dip galvanized steel and interstitial-free (IF) substrate with alkaline mud adhesion were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), and linear polarization. The results show that non-uniform corrosion occurs on the galvanized steel and IF substrate during 250 h with the mud adhesion. The corrosion products on the galvanized steel are very loose and porous, which are mainly ZnO, Zn5(OH... 相似文献
36.
Yue-long Bai) Jun Xu) Zhi-feng Zhang) Wei-min Mao) Hong Xu) ) General Research Institute for Non-ferrous Metals Beijing China ) School of Materials Science Engineering University of Science Technology Beijing Beijing China ) Research Center for Foundry Engineering North University of China Taiyuan China 《北京科技大学学报(英文版)》2009,16(4):422-426
The effect of injection pressure, piston velocity, and the forming temperature of semisolid slurry on the filling behavior of the semi-solid A356 aluminum alloy was investigated by simulation methods. The simulation results show that these processing parameters have an important effect on the filling behavior of the semi-solid A356 aluminum alloy. The slurry flows steadily in the cavity when the injection pressure, the piston velocity, and the forming temperature are low, but it is prone to turbulent flow w... 相似文献
37.
Guo-jun Wang ) Bai-qing Xiong) Yong-an Zhang) Zhi-hui Li) Pei-yue Li) ) State Key Laboratory for Fabrication Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing China ) Northeast Light Alloy Co. Ltd. Harbin China 《北京科技大学学报(英文版)》2009,16(4):427-431
The microstructure of the as-cast 2D70 aluminum alloy and its evolution during homogenization were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) analysis. The results indicate that the microstructure of the as-cast 2D70 aluminum alloy mainly consists of the dendritic network of aluminum solid solution and intermetallic compounds (Al2CuMg, Al2Cu, Al9FeNi, Cu2FeAl7... 相似文献
38.
Shuang Kuang) Yong-lin Kang) Hao Yu) Ren-dong Liu) ) School of Materials Science Engineering University of Science Technology Beijing Beijing China ) Technology Center Anshan Iron & Steel Group Corporation Anshan China 《北京科技大学学报(英文版)》2009,16(4):393-398
A more accurate estimation of stress-strain relationships for martensite and ferrite was developed, and the modified law of mixture was used to investigate the stress-strain partitioning of constituent phases in dual phase (DP) steels with two different martensite volume fractions. The results show that there exist great differences in the stress-strain contribution of martensite and ferrite to DP steel. The stress-strain partitioning coefficient is not constant in the whole strain range, but decreases with... 相似文献
39.
Comprehensive assessment on dynamic roof instability under fractured rock mass conditions in the excavation disturbed zone 总被引:3,自引:0,他引:3
Xing-ping Lai ) Fen-hua Ren) Yong-ping Wu Mei-feng Cai) ) Energy School Xi’an University of Science & Technology Xi’an China ) School of Civil Environmental Engineering University of Science Technology Beijing Beijing China ) Key Laboratory of Western Mine & Hazard Prevention China Ministry of Education China 《北京科技大学学报(英文版)》2009,16(1):12-18
The damage process of fractured rock mass showed that the fracture in rocks induced roof collapse in Yangchangwan Coal Mine,China.The rock mass was particularly weak and fractured.There occurred 6 large-scale dynamical roof falls in the excavation disturbed zone (EDZ) with the collapsing volume of 216 m3.First,the field detailed geological environment,regional seismic dy-namics,and dynamic instability of roadways were generally investigated.Second,the field multiple-index monitoring measurements for detecting the deep delamination of the roof,convergence deformation,bolt-cable load,acoustic emission (AE) characteristic pa-rameters,total AE events,AE energy-releasing rate,rock mass fracture,and damage were arranged.Finally,according to the time-space-strength relations,a quantitative assessment of the influence of rock-mass damage on the dynamic roof instability was accomplished. 相似文献
40.
Di-feng Wu) Shu-sen Cheng) Zi-jian Cheng) ) School of Metallurgical Ecological Engineering University of Science Technology Beijing Beijing China ) Steelmaking Plant Jiuquan Iron Steel Co. Ltd. Jiayuguan China 《北京科技大学学报(英文版)》2009,16(1):25-31
The key to reduce shell breakout in the continuous casting process is to control shell thickness in the mold.A numerical simulation on the turbulent flow and heat transfer coupled with solidification in the slab mold using the volume of fluid (VOF) model and the enthalpy-porosity scheme was conducted and the emphasis was put upon the flow effect on the shell thickness profiles in longitudinal and transverse directions.The results show that the jet acts a stronger impingement on the shell of narrow face,which causes a zero-increase of shell thickness in a certain range near the impingement point.The thinnest shell on the slab cross-section locates primarily in the center of the narrow face,and secondly near the comer of the wide face.Nozzle optimization can obviously increase the shell thickness and make it more uniform. 相似文献