YANG Quanmin KANG Mokuang Northwestern Polytechnical University
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Xi'an
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China YANG Quanmin
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Dept.of Material Science and Engineering
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Zhejiang University
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Hangzhou 310027
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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.
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bainitic
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null
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null
ZHAO Xinbing Zhejiang University
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Hangzhou
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China LCKEK Institut fur Metallkunde und Metallphysik der RWTH Aachen
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Germany Department of Materials Scicnce and Engineering
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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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null
林薇薇
中国腐蚀与防护学报
聚脲聚氨酯环氧涂料用於混凝土钢筋防腐蚀的研究林薇薇（浙江大学高分子系杭州３１００２７）钢筋混凝土建筑物耐久性下降的主要原因之一是增强钢筋的腐蚀。因为混凝土是多孔性凝胶体，空气中的氧、湿气和其它腐蚀介质能通过孔隙和细裂缝侵蚀钢筋，而钢筋变成铁锈时体积要增大２～４倍，结果产生内应力，使混凝土开裂，又进一步加剧腐蚀，造成钢筋混凝土构件破损失效。为此，目前已采用一些方法来减缓钢筋的腐蚀速度［１］。钢?...
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null
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Epoxy；Polyurea
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Polyurethane
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Concrete
涂江平
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李志章
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毛志远
中国腐蚀与防护学报
Ｎｉ－１３Ｃｒ－０．５Ｃｅ合金在５７５℃Ｃｌ_２－Ｈ_２Ｏ混合气氛中的腐蚀行为涂江平，李志章，毛志远（浙江大学杭州３１００２７）１引言关于合金在干氯气或含氯的氯化气氛中的腐蚀行为已有报导［１～３］，而在实际生产中，液氯经雾化后往往存在少量水份，使腐蚀环境变得复杂，尤其在高温下腐蚀条件进一步恶化［４］．高温氯气环境中少量水蒸气的存在对合金腐蚀行为的影响是复杂的．在５５０℃以下时水蒸气会加速镍基合?...
关键词:
null
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Internal chlorination
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Ni-Cr alloy
涂江平
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毛志远
,
李志章
中国腐蚀与防护学报
Ｎｉ－Ｃｒ－Ｃｅ合金经７００℃空气预氧化后在高温氯气中的腐蚀行为涂江平，毛志远，李志章（浙江大学杭州３１００２７）改善合金在高温含卤素气氛中的抗腐蚀性能，可以由形成和维持化学性质稳定、结合强度高和完整性好的表面膜来实现［１］．然而在较高氯分压的高温环境中Ｎｉ－Ｃｒ合金表面所形成的腐蚀膜难以具有保护作用，不能有效地阻碍Ｃ１２的继续侵蚀，因而使合金表现出很高的腐蚀速度．采用预氧化工艺使合金表面形?...
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