ZHONG Jiaxiang ZHENG Xiuhua XU Zongrui Beijing Institute of Technology
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Beijing
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ChinaBAI Dezhong Nei Monggol Machine Works No.2
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Nei Monggol
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China Beijing Institute of Technology
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Beijing 100081
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China
金属学报(英文版)
Three types of alloy carbides have been observed in tempered steel 4335V:M_3C,M_7C_3 and M_4C_3.The precipitation temperatures are 200—700,400 and 500 ℃ respectively.The com- position,morphologies and distribution patterns of the carbides as well as the relationship be- tween them and as-quenched substructures have been investigated.The influence of the car- bides on the low temperature impact toughness of the steel has also been discussed.
关键词:
steel 4335V
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null
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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