LU Feng CAO Fengyu LI Chengji University of Science and Technology Beijing
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Beijing
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ChinaZHANG Yongxiang CHEN Yonggang Beijing Institute of Machine Tools
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Beijing
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China Faculty of Metallograph
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University of Science and technology Beijing
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Beijing 100083
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China
金属学报(英文版)
Effect of Ca on hardenability and CCT diagram of steel 58CrV has been investigated by means of end-quenching and thermal expansion.An addition of 0.006 wt-%Ca to the steel may improve the hardenability,reduce the critical cooling rate of transformation of pearlite or bainite under continuous cooling and increase the M_s.AES analysis showed that Ca segre- gates markedly along austenitie grain boundaries,and accelecrates the segregation of C,Cr and Si.It is believed that besides towards deoxidizing and desulphurizing as well as improving sulphide morphology,a trace of Ca in steel 58CrV behaves towards microalloying.
关键词:
Ca
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null
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null
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null
李开明
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李亚洲
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冯维贵
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林长
量子电子学报
doi:10.3969/j.issn.1007-5461.2007.05.014
采用非线性反馈控制,用附加了带参数的正弦项对Chen系统进行了有效的控制.随着参数k的逐渐增大,系统的动力学行为呈现出一系列的变化.数值研究结果表明:随控制参数的增大,驱动信号的强度渐大,混沌系统由混沌运动到周期轨道,最终到一相点.
关键词:
混沌
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Chen系统
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不动点
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Lyapunov指数
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反馈控制
SONG Qiang
钢铁研究学报(英文版)
Prediction of the alkalinity is a difficult problem during the process of sintering .Whether the level of he alkalinity of it is successful or not direct relates to the quality of sinter.By now,there isn’t a very good method due to the high complexity ,high non-linear, strong coupling, high delay-time and etc.A grey support vector machine model was proposed on the basis of the models.The fluctuation of data sequence is weakened by the grey theory and the support vector machine is capable of processing non-linear adaptable information, and the grey support vector machine is a combination of those advantages. The results reveal, the alkalinity of sinter can be accurately predicted through this model by reference to small sample and information. It was concluded that the grey support vector machine model is effective with the advantages of high precision, less samples required and simple calculation.
关键词:
alkalinity of sinter;grey least support vector machine;prediction;the sintering process;grey model.
Wear
Erosion-corrosion wear is a common failure type for many mining machine parts. This paper introduces the erosion-corrosion wear resistant, nickel based alloy coating, which is manufactured onto AISI 1045 steel by laser cladding technology. X-ray diffraction, scanning electron microscopy (SEM) and microhardness testing were used to investigate the microstructure and hardness of the coating. After that, erosion-corrosion wear experiments were carried out on an MSH type erosion-corrosion wear tester to study the erosion-corrosion wear characteristics of the laser clad coating. 420 stainless steel was also tested under the same conditions as a contrast specimen. The slurry was made up of water and quartz, while sulphuric acid was added to create corrosive condition. Experiments were arranged to test the relation between erosion-corrosion wear rate, the acid concentration and slurry erosion speed. Finally this gaper introduces the application of laser cladding technology to balance plates of slurry pumps used in underground mining. (C) 1997 Elsevier Science S.A.
关键词:
laser cladding;coating;erosion-corrosion wear;synergism
