材料期刊网

VALENCE ELECTRON STRUCTURE OF HIGH PROPERTY HIGH SPEED RESISTANCE STEEL AND ITS COMPOSITION DESIGN

Z.L. Li1 , 2) , C.X.Ma2) and Z.L.Liu1) 1) Department of Materials Science and Engineering , Liaoning Institute of Technology , Jinzhou 121001 , China 2) Collage of Science , Northeast University , Shenyang , 110006 , China

金属学报(英文版)

Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsin high speed impact resistance ( HSIR) steel. According tothese va lenceelectron structure parametersitis deduced thatthe alloying elements of high propertyHSIRsteelshould be Mn, Cr, Ni and Mo. The microscopicstructure ofthesteel with this compositionisthe mixtureof martensite, bainiteand austeniteafter quenching andlow tem peraturetempering.Itspropertiesare:σb = 1750 MPa,σ0 2 = 1460 MPa,δ5 = 12 7 % , AKV(at 40 ℃, cross direction) = 21J, which exceed the requirement of design. For the thick plateof high property HSIRsteel,itissuggestedto add alittleamountof Cu on thebasisofabovecomposition .

关键词: High speed impact resistancesteel , null

Bibliography of Science and Technology of Rare EarthsPublished in China (2001)

稀土学报(英文版)

关键词:

Bibliography of Science and Technology of Rare EarthsPublished in China (2001)

稀土学报(英文版)

关键词:

Bibliography of Science and Technology of Rare EarthsPublished in China (2001)

稀土学报(英文版)

关键词:

Bibliography of Science and Technology of Rare EarthsPublished in China (2001)

稀土学报(英文版)

关键词:

Bibliography of Science and Technology of Rare EarthsPublished in China (2001)

稀土学报(英文版)

关键词:

Bibliography of Science and Technology of Rare EarthsPublished in China (2001)

稀土学报(英文版)

关键词:

Change in Carbon Dioxide (CO2) Emissions From Energy Use in China′s Iron and Steel Industry

SUN Wenqiang , CAI Jiuju , MAO Hujun , GUAN Duojiao

钢铁研究学报(英文版)

As the largest energy consuming manufacturing sector and one of the most important sources of carbon dioxide (CO2) emissions, the China′s iron and steel industry has paid attention to the study of changing trend and influencing factors of CO2 emissions from energy use. The logarithmic mean Divisia index (LMDI) technique is used to decompose total change in CO2 emissions into four factors: emission factor effect, energy structure effect, energy consumption effect, and steel production effect. The results show that the steel production effect is the major factor which is responsible for the rise in CO2 emissions; whereas the energy consumption effect contributes most to the reduction in CO2 emissions. And the emission factor effect makes a weak negative contribution to the increase of CO2 emissions. To find out the detailed relationship between change in energy consumption or steel production and change in CO2 emissions, the correlation equations are also proposed.

关键词: CO2 emissions , energy use , LMDI technique , steel production , energy consumption

Key R&D activities for development of new types of wrought magnesium alloys in China

Transactions of Nonferrous Metals Society of China

Many researchers in China are actively engaged in the development of new types of wrought magnesium alloys with low cost or with high-performances and novel plastic processing technologies. The research activities are funded primarily through four government-supported programs: the Key Technologies R&D Program of China, the National Basic Research Program of China, the National High-tech R&D Program of China, and the National Natural Science Foundation of China. The key R&D activities for the development of new wrought magnesium alloys in China are reviewed, and typical properties of some new alloys are summarized. More attentions are paid to high-strength wrought magnesium alloys and high-plasticity wrought magnesium alloys. Some novel plastic processing technologies, emerging in recent years, which aim to control deformation texture and to improve plasticity and formability especially at room temperature, are also introduced.

关键词: wrought magnesium alloy;microstructure;properties;alloy designing;plastic deformation;research projects;y-zr alloys;mechanical-properties;mg-4y-4sm-0.5zr alloy;grain-refinement;rare-earth;microstructure;gd;phase;temperature;evolution

(alpha-PbO2-type nanophase of TiO2 from coesite-bearing eclogite in the Dabie Mountains, China

American Mineralogist

A natural high-pressure phase of titanium oxide with alpha-PbO2-structure has been found in omphacite from coesite-bearing eclogite at Shima in the Dabie Mountains, China. High-resolution transmission electron microscope observations have revealed an orthorhombic lattice, corresponding to alpha-PbO2-type TiO2, with cell parameters a = 0.461 nm, b = 0.540 nm, c = 0.497 nm and space group Pbcn. It occurs as nanometer-thick (< 2 nm) lamellae between multiple twinned rutile crystals, providing additional evidence of very high-pressure, metamorphism at 7 GPa, 900 degrees C. This implies subduction of continental material to a depth of more than 200 kilometers. alpha-PbO-type TiO2 could be an extremely useful index mineral for ultrahigh-pressure.

关键词: high-pressure phase;ries crater;rutile;polymorph;titanium