YANG Quanmin KANG Mokuang Northwestern Polytechnical University
,
Xi'an
,
China YANG Quanmin
,
Dept.of Material Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China
金属学报(英文版)
The chemical driving forces for the phase transformation from austenite in three different car- bon-depleted regions into ferrite with the identical composition have been derived respectively. The starting temperature of bainitic transformation,B_s,has also been calculated according to the shearing mechanism of bainitic transformation in carbon-depleted regions of austenite. The maximum driving forces for banitic transformation at B_s in both 3% Cr and the CrMo steels were obtained.It was shown that the proposed shearing mechanism of the bainitic trans- formation is thermodynamically possible.
关键词:
bainitic
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null
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ZHAO Xinbing Zhejiang University
,
Hangzhou
,
China LCKEK Institut fur Metallkunde und Metallphysik der RWTH Aachen
,
Germany Department of Materials Scicnce and Engineering
,
Zhejiang Univer sity
,
Hangzhou 310027
,
China
金属学报(英文版)
Most of the available methods for the calculation of the three dimensional(3D)grain size dis- tribution functions(SDF)are based on the S model and lead a grave systematical error.The origin is the basic supposition of spherical grains in the S model,which does not correspond with the feature of real grains.A new model called A model is developed based on the hypothe- sis of polvhedral grains.The probability functions of the A model and the method to calculate the 3D SDFs using the A model are given in the present paper.The theoretical analyses and experimental tests have demonstrated that the A model reduces the systematical error radical- ly.It is nearly as simple as the so far used S model,but gives much better results in repro- ducing of 3D SDFs from the measured ID or 2D SDFs.
关键词:
grain size
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null
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null
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