LI Cheng Beijing Central Design and Research Institute for Non-Ferrous Metallurgical Industry
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Beijing
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ChinaLIU Chunpeng
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Kunming Institute of Technology
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Kunming
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China LI Cheng
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Metallurgical Dept.No.l
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Beijing Central Design and Research Institute for Non-Ferrous Metallurgical Industry
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Beijing 100038
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China
金属学报(英文版)
The rate equation of reaction between PbS and PbO is dα/dt=kx_(PbS)~3 x_(PbO)~(-2).A transition product, PbSO_4·2PbO,is found by X-ray diffraction analysis.The reaction mechanism was dis- cussed on the basis of electron transfer.
关键词:
kinetics
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null
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null
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LIU Rixin NING Baolin ** Dept.of Metallurgy
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Kunming Institute of Technology
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Kunming
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650093
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China*** Dept.of Thermal Energy
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Northeast University of Technology
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Shenyang
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110006
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China+ To whom correspondence should be addressed
材料科学技术（英）
This paper provides a mathematical model for the billet reheating process in furnace.A new optimum method is brought up that the objective function is the integral value of enthalpy increasing process of a billet.Different delays are simulated and calculated,some proper delay strategies are ob- tained.The on-line computer control model is de- veloped.The real production conditions simulated, the temperature deviation of drop out billet from the target temperature is kept within±15℃.
关键词:
reheating furnace
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By LIU Zhonghua LIU Chunpeng Department of Metallurgy
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Kunming Institute of Technology
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Kunming
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650093
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China.To whom correspondence should be addressed.
材料科学技术（英）
Reduction kinetics of Ni_3S_2 was experimen-tally studied by following the time required forcompletion of the hydrogen reduction reaction inthe presence of calcium oxide.A simple empiricalintegration equation,derived for describing the ef-fect of CaO/S molar ratio,temperature,hydrogenconcentration and the average diameter ofNi_3S_2 grains,may be shown as following:t_(X=1)=2.317×10~(-6)d_(Ni_3S_2) C_(H_2)~(-1)β~(-2.29)e~(13710/T),minThe reduction reaction is of first order with respectto hydrogen concentration,and the apparent reac-tion activation energy is 114.0 kJ/mol.A great ma-jority of metallic Ni reduced from Ni_3S_2 is distrib-uted in the products evenly.
关键词:
kinetics
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null
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TAO Dongping LIU Chunpeng ** Dept.of Metallurgy
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Kunming Institute of Technology
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Kunming
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650093
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China+ To whom correspondence should be addressed
材料科学技术（英）
The rate processes of oxidative dearsenication of niccolite ore in microwave oven and in conventional furnace were measured with thermogravimetric technique.The results show that the dearsenication rate of niccolite ore with microwave heating becomes faster than that with conventional heating. Under the conditions of an approximate linear heating and a definite air flow,the oxidative dearsenication process of niccolite ore is mainly controlled by interfacial chemical reaction.The ex- perimental data are in agreement with the kinetic model of linear heating as follows: In{[1-(1-α)~(1/3)]/T}= In (PAM)/(r_oρφE)(1-(RT)/E)-E/(RT) Thus the apparent activation energies of oxidative dearsenication of the niccolite ore containing differ- ent additions have been obtained from the model.
关键词:
kinetics
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D.Eylon
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S.R.Seagle
材料科学技术（英）
The state of Ti research, development and industry is reviewed in this article. The fifty-year anniversary of Ti technology commercialization in the USA provides an opportunity for a historical perspective. Incorporation of "information-age" tools into alloy development, processing, and production invigorates the technology. Consolidation, diversification and globalization have been transforming the Ti industry in the recent years.
关键词:
Yanwu Xu
材料科学技术（英）
Using mathematical plasticity theories, universal formability (UF) technology has been developed and applied in the automotive stamping engineering and production. As a formability analysis tool, this technology is the major methodology for the development of stamping expert system (solution provider) for (a) product design and feasibility analysis, (b) material automatic selection using nomograms, (c) draw die design using pre-models, and (d) UF and robustness analysis of die performance in finite element analysis (FEA) environment.
关键词:
G.Montay
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A.Cherouat
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A.Nussair
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J.Lu
材料科学技术（英）
Residual stress in coatings is the result of individual particle stress. Their effects may be either beneficial or detrimental, depending upon the magnitude, sign and distribution of the stresses with respect to the external load. Tensile stress which exceeds the elastic limit causes cracking in surface coatings or at the interface between the substrate and the coat. Compressive stress, in general, has a beneficial effect on the fatigue life, crack propagation, coating adhesion and on the durability of the top coat during service. Compressive residual stresses can increase the number of cycles before crack initiation begins through a mean stress effect. Temperature gradients which occur during solidification and subsequent cooling are the principal mode of internal stresses generation. Some parameters influence the residual stress field of both the coating and the substrate. Substrate nature, spraying temperature, thickness of the coat layer, substrate preparation (grit blasting conditions), and velocity of the splats are in the relation with the quality of the coating. In this work, we will describe the role playing by the ceramics coating elaboration on the residual stress gradient in depth of the component. The incremental hole drilling technique has been developed to determine the residual stress gradient in depth of the coat and substrate which must be used with particularly conditions. This new technology has been employed on zirconia, alumina and tungsten carbide plasma sprayed coating.
关键词:
Coating
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