检索结果-南通市图书馆

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical engineering school.university of {2. and technology beijing, beijing 100083. china Metallurgical engineering School University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

The precipitation and effect of nano nitrides in HSLC steel

在线全文

学校读者我要写书评

暂无评论

science china(Technological sciences) 2008年第7期51卷 989-998页

作者： FU Jie1, LIU YangChun1,2.& WU HuaJie1,3 1 School of Metallurgical and Ecological engineering, university of science and technology beijing,{2. 2.Shougang technology research institute, Shougang (Group) Corporation, beijing 100041, china 3 Metallurgical engineering research institute, university of science and technology beijing,{2. 1. School of Metallurgical and Ecological engineering University of Science and Technology Beijing Beijing 100083 China 2. Shougang technology research {2. Shougang (Group) Corporation Beijing 100041 China 3. Metallurgical engineering research {2. University of Science and Technology Beijing Beijing 100083 China

The existing forms of N and Al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of AlN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into AlN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. Aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043%. The precipitation of AlN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is AlN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure AlN, but have complex compositions.

关键词： thin slab casting and rolling high strength low carbon steel AlN nano nitride precipitation strengthening

Producing Calcium-Bearing Mullite Thermal-Insulating Refractories by Kyanite

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 50-53页

作者： Wen Ni (Resources engineering School, university of science and technology beijing,{2.) Resources engineering School University of Science and Technology Beijing Beijing 100083 China

To improve the physical properties, a series of experiments have been camed out to produce calcium-bearing mullite thermal-insulating refractories by using kyanite as major raw materials. The experiments were carried out by a foaming technique and using white cement as a combing agent. The results show that the calcium-bearing mullite refractory has much better physical properhes than traditional clay refractory and high-alumina refractory.

关键词： mullite thermal-insulating refractory kyanite

A New Safety Electric Initiating System

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 306-308页

作者： Daze Lin(Resource engineering School, university of science and technology beijing,{2.) Univ of science and technology Beijing Beijing China

Based on the analysis of weakness on the safety of traditional electric detonators, a BJ-l safety electric detonator initiatingsystem and its corresponding safe examination technique were successfully developed. By leading false foot wires and taking advantageof the transmitting frequency band of Mo-Zn ferrite, detonators in this new system can completely impede the direct induction of outsidecrosstalk that may cause casual firing in the ordinary as well as eleclromagnetic ones. Possible causality by lightning was discussed. Results are presented, of its safety tests on resistance to direct and alternating current, electrostatic, and crosstalk induced by damp leakagein saturated salty water.

关键词： electric detonator blasting engineering, electric initiating system, safety

The mathematical model of wetting angle of heterogeneous nucleation

在线全文

学校读者我要写书评

暂无评论

science china(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2.& ZHAO Pei3 1. School of Metallurgical and Ecological engineering, university of science and technology beijing,{2. 2. School of Material science, university of science and technology beijing,{2. 3. Central Iron and Steel research institute, beijing 100081, china 1. School of Metallurgical and Ecological engineering University of Science and Technology Beijing 100083 Beijing China 2. School of Material science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel research institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2.3 are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

Nonlinear Theory on Dynamic Controlling Interface Patterns DuringSolidification of a Dilute Binary Alloy

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 253-258页

作者： Zidong Wang Hanqi Hu(Material science and engineering School, {2. of science and technology beijing, beijing 100083. china) Material science and engineering School University of Science and Technology Beijing Beijing 100083 China

In non-equilibrium nonlinear region, the nonlinear equations of time dependence of perturbation amplitude at the solid/liquidinterface during solidification of a dilute binary alloy are established on the base of assuming that there is local equilibrium at the solid/liquid interface and considering that curvature, temperature and composition at the solid/liquid interface which are related to the perturbation amplitude are nonlinear. As a result, patterns at the solid/liquid interface during solidification process, which is from nonsteadystate to steady state can be controlled by these nonlinear equations.

关键词： nonlinearity solidification, dilute binary alloy, dynamic control

Microstructural Features During Strain Induced Ferrite Transformation in 08 and 2.Mn Steels

在线全文

学校读者我要写书评

暂无评论

Journal of university of science and technology beijing 2001年第2期8卷 105-110页

作者： Ping Yang, Feng-e Cui, Fuming Wang (Materials science and engineering School,{2., beijing 100083. china) (Metallurgy School,{2., beijing 100083. china) Univ Sci & Technol beijing Mat Sci & Engn Sch Beijing 100083 Peoples R China Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

The microstructure evolution during strain induced ferrite transformation was followed in thermal-simulation tests of clean 08 and 2.Mn steels. The influences of carbon equivalence and initial austenite grain size on ferrite grain refinement and the volume fraction of ferrite during straining were inspected. The results revealed that the accelerating effect of ferrite transformation by strain was increased as the carbon equivalence decreased. However, finer ferrite grains were obtained at higher carbon content. At strain of similar to1.5 ferrite grains less than 3 mum and 2.mum can be obtained in 08 and 2.Mn steels respectively. Whereas the ferrite grain refinement in 08 steel was due to both effects of strain induced transformation and ferrite dynamic recrystallization, that in 2.Mn was mainly due to strain induced transformation. Heavy strain can produce fine ferrite grains in coarse austenite grained 08 steel, but it would lead to band microstructure in coarse austenite grained 2.Mn.

关键词： clean carbon steel strain induced transformation grain refinement ferrite dynamic recrystallization

Preparation of semi-solid AlSi7Mg alloy slurry with big capability

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2010年第6期29卷 642-645页

作者： LI Sha and MAO Weimin School of Materials science and engineering,{2. of science and technology beijing,beijing 100083.china School of Materials science and engineering University of Science and Technology Beijing Beijing China

Semi-solid AlSi7Mg alloy slurry was prepared by low superheat pouring and weak traveling-wave electromagnetic *** effects of pouring temperature and stirring power on the microstructure of AlSi7Mg alloy slurry were *** results show that the semi-solid AlSi7Mg alloy slurry of 5 kg can be *** new technology can save energy and make the pouring process *** the pouring temperature is decreased at a stirring power of 0.41 kW,the shape of primary α-Al grains gradually changes from dendritic-like to *** the alloy melt is poured at the temperature（630°C） with a certain superheat,the pouring process becomes easier,and the spherical microstructure of AlSi7Mg alloy slurry can be prepared by the weak traveling-wave electromagnetic *** the pouring temperature is 630°C,increasing the stirring power appropriately can result in better spherical primary α-Al grains,but if the stirring power is increased to a certain value（1.72.kW）,the shape of primary α-Al grains does not obviously improve when the stirring power is continually increased.

关键词： aluminum alloys metal forming semisolid slurry electromagnetic stirring microstructure

A New Genetic Algorithm Based on Niche Technique and Local Search Method

在线全文

学校读者我要写书评

暂无评论

Journal of university of science and technology beijing 2001年第1期8卷 63-68页

作者： Jinwu Xu, Jiwen Liu Mechanical engineering School, university of science and technology beijing,{2. Univ Sci & Technol beijing Sch Mech Engn Beijing 100083 Peoples R China

The genetic algorithm has been widely used in many fields as an easy robust global search and optimization method. In this paper, a new generic algorithm based on niche technique and local search method is presented under the consideration of inadequacies of the simple genetic algorithm. In order to prove the adaptability and validity of the improved genetic algorithm, optimization problems of multimodal functions with equal peaks, unequal peaks and complicated peak distribution are discussed. The simulation results show that compared to other niching methods, this improved genetic algorithm has obvious potential on many respects, such as convergence speed, solution accuracy, ability of global optimization, etc.

关键词： genetic algorithm (GA) niche technique local search method