HUANG Qizhong
,
YANG Qzaoqin and WU Lijun(Powder Metallurgy Research institute
,
Central Sonth University of Technology
,
Changsha 410083
,
China Materials Research and Test Center
,
Hnnan University
,
Changsha 410082
,
ChinaLab. of Atomic Imaging of Solids
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang110015
,
ChinaState Key Laboratory for Corrosion and Protection
,
Institute of Corrosion and Protection of Metals
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)Manuscript received 4 August 1995
,
in revised form 6 April 1996
金属学报(英文版)
A Preliminary study of the effect of silicon additive on the structure and properites of C-B_4C-SiC composite was conducted. A liquid Phase has formed and the liquid Si reacts with C to form SiC at the grain boundary when sintering, which accelerates the sintering process and retards the grain growth. Consequently, the density and strength of the composite increase markedly. And the increase in the density increases the oxidation resistance and decreases the specific resistance of the composite. Furthermore,the C-B_4 C-SiC composite has good heat-shock resistance. The phenomena may be dueto the strengthening and toughening of microcracks.
关键词:
:Si additive
,
null
,
null
CHEN Yong
,
et al
钢铁研究学报(英文版)
The dynamic soft reduction technology for 360mm×450mm bloom casting and its application results at PISCO (Panzhihua Iron & Steel Co.) were presented. In order to analyze the influence of the soft reduction on internal defects of bloom, such as center porosity and central segregation, experiment for contrasting process with or without soft reduction for bloom was investigated. The operation shows that after applying the soft reduction of bloom alloy steel, the ratio of center porosity whose defect level is below 1.0 increased from 66.67% to 85.71%, ratio of central segregation whose defect level is below 1.0 increased from 94.44% to 100%, ratio of central shrinkage cavity which is free increased from 88.89% to 96.42%, and central segregation index of carbon decreased from mean value of 1.15 to 1.05. These results have provided important technology supports for PISCO to optimize the steel product structure, and to improve the production of high quality, property, and value added products.
关键词:
continuous casting bloom;dynamic soft reduction;alloy steel;internal quality
Applied Physics a-Materials Science & Processing
The terahertz dielectric response of LuFe(2)O(4) is investigated by terahertz time-domain spectroscopy over a temperature range of 6-290 K. It is revealed that besides the central mode associated with the charge-ordered state, a soft TO(1) mode at below similar to 240 K is identified indicating the existence of displacing ferroelectricity, in addition to the charge-ordering-induced ferroelectricity at below 320 K. The anomaly of the soft mode at similar to 180 K reflects the magnetoelectric correlation between the soft TO(1) mode and the spin/charge fluctuations revealed recently. Finally, the magnetic property at below similar to 240 K is discussed.
关键词:
system lufe2o4;charge;polarization
D.Eylon
,
S.R.Seagle
材料科学技术（英文）
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:
QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China
金属学报(英文版)
The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.
关键词:
stress corrosion cracking
,
null
,
null
,
null
Yanwu Xu
材料科学技术（英文）
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:
