材料期刊网

1. 首页
2. 检索结果页

原词结果 | 译词结果

Kinetic Model of εCu Particle Dissolution in Welding Induced HAZ of CopperContaining Steel

WANG Qingfeng , CHAI Feng , CAI Jianwei , PAN Tao , SU Hang

钢铁研究学报(英文版)

The kinetics of εCu particle dissolution in the matrix of heat affected zone (HAZ) during welding of a coppercontaining steel was determined by assembling the welding temperaturetime program into a modified Whelan′s solution. The particle dissolution dependence on the degree of “superheating” above the equilibrium transformation is demonstrated from the model. In terms of volume fraction of particle dissolution, the HAZ may be classified into three zones, including the undissolving zone, the partially dissolving zone, and the completely dissolving zone, respectively. The numerical solution was in good agreement with the experimental examination finding. The results of model can be used to quantitatively map the εCu dissolution zone dependence on the peak temperature of welding thermal cycles and understand the evolution of this transformation during welding.

关键词: εCu;particle dissolution;kinetics;welding;steel

Influence of Iron Ore Characteristics on FeO Formation During Sintering

WU Shengli , WANG Qingfeng , BIAN Miaolian , ZHU Juan , LONG Fangyi

钢铁研究学报(英文版)

The influence of iron ore characteristics on FeO formation during sintering was examined mainly in terms of chemical composition and the melting characteristics of iron ores. Statistical regression and Xray diffraction were used to further explain the specific effect of iron ore characteristics on FeO formation. The results indicate that LOI (loss on ignition) in iron ores have a positive influence on FeO formation by promoting the sintering process of Fe2O3 decomposing and reducing. Silica contents in iron ores play a determining role in final content of FeO in sinter. The melting characteristics of iron ores significantly affect FeO formation during sintering.

关键词: iron ore characteristic , chemical composition , melting characteristic , FeO formation

Effect of Tempering Temperature on Microstructure and Mechanical Properties of Steel Containing Ni of 9%

ZHAO Xiqing , PAN Tao , WANG Qingfeng , SU Hang , YANG Caifu , YANG Qingxiang

钢铁研究学报(英文版)

Mechanical properties of quenching, intercritical quenching and tempering (QLT) treated steel containing Ni of 9% were evaluated from specimens subject to various tempering temperatures. The detailed microstructures of steel containing Ni of 9% at different tempering temperatures were observed by optical microscope (OM) and transmission electron microscope (TEM). The volume fraction of austenite was estimated by XRD. The results show that high strength and cryogenic toughness of steel containing Ni of 9% are obtained when the tempering temperature are between 540 and 580 ℃. The microstructure keeps the dual phase lamellar structure after the intercritical quenching and there is cementite created in the Nirich constituents when tempering temperature is 540 ℃. When tempering temperatures are between 560 and 580 ℃, the reversed austenites (γ′) grow up and the dual phase lamellar structure is not clear. The γ′ becomes instable at 600 ℃. When tempered at temperature ranging from 500 to 520 ℃, the increase of dislocation density in the lamellar matrix makes both tensile strength and yield strength decrease. When tempered at 540 ℃ and higher temperature, the yield strength decreases continuously because the C and alloying elements in the matrix are absorbed by the cementite and the γ′, so the yield ratio is decreased by the γ′. There are two toughness mechanisms at different tempering temperatures. One is that the precipitation of cementite absorbs the carbon in the steel which plays a major role in improving cryogenic toughness at lower temperature. Another is that the γ′ and the purified matrix become major role at higher tempering temperature. When the tempering temperature is 600 ℃, the stability of γ′ is decreased quickly, even the transformation takes place at room temperature, which results in a sharp decrease of CharpyV impact energy at 77 K. The tempering temperature range is enlarged by the special distribution of cementite and the lamellar structure.

关键词: steel containing Ni of 9% , tempering temperature , cementite , reversed austenite , cryogenic toughness

Physical Simulation and Experimental Examination of εCu Particles Dissolution Evolution During Welding of Copper Precipitation Strengthening Steel

WANG Qingfeng , SHANG Chengjia , CHEN Dawei , CAI Jianwei , CHEN Weichang

钢铁研究学报(英文版)

The kinetics of εCu particles dissolution in the matrix during welding of a copperprecipitation strengthening steel was determined by a combination of GleebleTM physical simulation, TEM examination and hardness measurement. The εCu particles underwent a coarsening and part dissolution and then complete dissolution reaction as the peak temperature increased from 750 to 1 000 ℃, which resulted in the decrease in the number density of εCu particles and hardness in the heataffected zone (HAZ). The results can be used to understand the evolution of this transformation and a softening behavior of the HAZ during welding of this type of steel.

关键词: εCu particle dissolution;hardness;kinetics;steel;welding;physical simulation

出版年份

刊物分类

相关作者

相关热词