LI Jian SUN Fuyu Central Iron and Steel Research Institute
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Beijing
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China Engineer
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Department No.4
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Central Iron and Steel Research Institute
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Ministry of Metallurgical Industry
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Beijing 100081
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China
金属学报(英文版)
The volume fraction of proeutectoid ferrite transformed from deformed austenite fv as a func- tion of isothermal time t has been investigated in 0.037% Nb microalloyed steel.The results show that lnln(1-fv)~(-1) vs Int relation does not follow the Avrami equation strictly and con- sists of two straight lines.By comparing the differences between the results and Cahn's theory, the authors' idea has been expounded.
关键词:
austenite deformation
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ZHU Ruihui WANG Yu HAN Qiyong SONG Weixi University of Science and Technology Beijing
,
Beijing
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China Engineer
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Institute of Precise and Special New Materials
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University of Science and Technology Beijing
,
Beijing 100083
,
China
金属学报(英文版)
The dependence of nodularization of graphite upon Ce content in RE bearing nodular cast iron,prepared by directional solidification,has been investigated by electrolytic extraction-radioisotope assay analysis of Ce in each phase of the iron together with measurement of nodulized graphite.Results show that the Ce occurs mainly as alloyed form. In the graphite phase,the Ce content is believed to be characterization of nodularization.The graphite would completely nodulized only the Ce is over a certain content in graphite phase.
关键词:
RE nodular cast iron
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CHEN Guosheng WU Bohua ZHOU Lecheng LI Yuqing Research Institute of Daye Steel Works
,
Huangshi
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China Engineer
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Research Institute of Daye Steel Works
,
Huangshi 435001
,
China
金属学报(英文版)
Because Nb accelerates the uniform distribution of MC phase and the grain refinement,as well as,increases the amount and stability of γ-phase,the tensile strength,ductility,stress rupture life and fatigue limit of Fe-30Ni-13Cr-1.2W-1.5Mo-2.5Ti-0.4AI superalloy at 650℃ can be improved with increase of Nb content up to 1.22 wt-%.The precipitation of small Laves phase particles dispersed along grain boundaries may be favourable to combined properties of the superalloy containing 1.22 wt-% Nb.It will be worsened only that the pre- cipitation of Laves phase particles'dispersed along grain boundaries may be favourable for combined properties of the superalloy containing 1.22 wt-% Nb.It will be worsened only that the precipitation of Laves phase is too more because of too high Nb content existhing.
关键词:
Nb
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