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Design of TRIP Steel With High Welding and Galvanizing Performance in Light of Thermodynamics and Kinetics

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Journal of Iron and Steel Research International 2007年第6期14卷 37-41页

作者： LI Lin DE COOMAN B C liu ren-dong VLEUGELS j ZHANG Mei SHI Wen School of Materials Shanghai University Shanghai 200072 China Postech Graduate School of Ferrous Technology Pohang University of Science and Technology Pohang 790784 South Korea Technique Center of Ansteel Ansteel Company Anshan 114001 Liaoning China Department of MTM Katholieke Universiteit Leuven Kasteelpark Arenberg 44 B-3001 Belgium

A new type of transformation induced plasticity （TRIP） steel with not only high strength and high ductility but also superior welding and galvanizing properties was designed and developed recently. Low carbon and low silicon content were preliminarily selected with the aim of meeting the requirements of superior quality in both welding and galvanizing. Phosphorus was chosen as one of the alloying elements, because it could reduce carbon activity in cementite and increase the stability of austenite. In addition, the possibility of phosphorus segregating at grain boundary was also discussed by thermodynamics as well as kinetics. Phase diagram was estimated at high temperature and the composition of the steel was then selected in the hyperperitectic range to avoid problems, which might occur in sheet steel continuous casting. Phase diagram in the *** temperature was estimated for the steel to obtain the starting temperature of fast cooling. For understanding the minimum rate of fast cooling, pearlite growth kinetics was calculated with self-developed diffusion coefficients of elements in grain boundary. Overaging temperature was determined through the calculation of To temperature by both equilibrium and para-equilibrium assumptions, which was different from the current determination, which is only based on an equilibrium estimation.

关键词： TRIP steel design thermodynamics kinetics weldability galvanization property

Two new Jurassic stoneflies (Insecta: Plecoptera) from Daohugou, Inner Mongolia, China

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Progress in Natural Science:Materials International 2008年第8期18卷 1039-1042页

作者： Yushuang liu, dong ren * College of Life Science, Capital Normal University, 105 Xisanhuanbeilu, Haidian District, Beijing 100037, China College of Life Science Capital Normal University 105 Xisanhuanbeilu Haidian District Beijing 100037 China

Two new genera and two new species of family Taeniopterygidae, Mengitaenioptera multiramis gen. et sp. nov. and Noviramonemoura trinervis gen. et sp. nov. are described. These fossils were collected from Daohugou Village (the Middle Jurassic), Inner Mongolia, China. Hitherto, these fossil species from Daohugou are the oldest taeniopterygids. Both simple and complex venations simultaneously occurred in this group, which reveals that the early diversification of taeniopterids was well underway by the Middle Jurassic. Therefore, we prefer to adopt the Comstock’s opinion that the venation of taeniopterids was derived from the simple venation of the older group (such as Palaeonemouridae) at much ancient geological time ago. Some of the descendants carried this simple venation; others evolved into complex venation with many additional crossveins and branches.

关键词： Plecoptera Taeniopterygidae Daohugou Inner Mongolia Middle Jurassic

The Development of Hot Rolled Automobile Beam Steel Plates 500L-Z With Excellent Surface Oxide Layer

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Journal of Iron and Steel Research International 2011年第S1期18卷 999-1003页

作者： SHI Xiao-guang,HAN Bin,XU Xin,dong Yi,liu ren-dong (An Gang Steel Co Ltd,Anshan 114001,Liaoning,China) An Gang Steel Co Ltd Anshan 114001 Liaoning Peoples R China

This paper has determined the compositions and hot rolling processes of the hot rolled beam steel plates with excellent surface oxide layer for automobiles by investigating the oxide layer forming principle and its influence factors,and the feature of the steel oxide *** microstructure,mechanical properties,oxide layer shape and structural composition of the steel plates are analyzed by using metallographic structures examination,SEM analyzing,X-ray diffraction instrument and mechanical properties *** result shows that the trial hot rolled frame steel plates have an excellent oxide layer adhesion,the Fe 3 O 4 proportions is greater than 85% in the oxide layer,and the oxide layer thickness is less than or equal to 10μ*** product has been trial-manufactured more than 100 thousands ton,and used to stamp the beam parts of automobiles straightly in no pickling *** oxide layer scarcely scales off from the steel plates,and the effect is remarkable.

关键词： automobile beam 500L-Z Fe 3 O 4 oxide layer

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夕线石成因讨论

岩石矿物学杂志 2022年第2期41卷 437-445页

作者：任留东中国地质科学院地质研究所北京100037

本文通过夕线石的结构、成分及产出状态,系统讨论和总结了其变质形成过程。含夕线石的变质岩原岩未必对应泥质岩,富夕线石岩石成分上更不能与任何的泥质岩成分对应。原岩本身富铝如多数泥质岩是形成夕线石非常有利的成分条件,但是,即使... 详细信息

本文通过夕线石的结构、成分及产出状态,系统讨论和总结了其变质形成过程。含夕线石的变质岩原岩未必对应泥质岩,富夕线石岩石成分上更不能与任何的泥质岩成分对应。原岩本身富铝如多数泥质岩是形成夕线石非常有利的成分条件,但是,即使有合适的温压条件,也未必能够形成夕线石,组分的差异性迁移才是夕线石形成的必要条件。夕线石的形成与变形、变质作用,尤其是深熔作用密切相关。浅色体、伟晶岩及花岗岩等均可通过变质、深熔作用演化而成。夕线石形成的关键是深熔作用中碱(土)金属的迁移、淋滤及其与硅铝组分的分离,从而造成局部Al_(2)O_(3)相对增加。夕线石尤其是毛发状夕线石对应于早期差异性变形-变质作用阶段。组分迁移过程中溶液或熔体组分的流动导致夕线石出现“应力定向”的假像、夕线石和相关矿物的聚集以及不同变质矿物的多个演化阶段。铝硅酸盐Al_(2)SiO_(5)的不同变体虽然成分相同,其所产出的岩石类型或环境仍有显著的差别,其形成不仅受温压条件控制,流体或熔体的酸碱性质也很重要,介质成分可影响到铝的配位。

关键词：夕线石深熔作用浅色体组分迁移、富集介质

南极拉斯曼丘陵长英质变质岩中磷灰石-斜方辉石组合的岩石学意义

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岩石矿物学杂志 2011年第5期30卷 961-966页

作者：任留东刘平中国地质科学院地质研究所北京100037

南极拉斯曼丘陵高级长英质变质岩中出现的磷灰石-斜方辉石(Ap-Opx)组合表明岩石经历了麻粒岩相条件下的变质作用,长英质片麻岩发生了强烈的脱水深熔作用。随着熔体的迁出,长英质片麻岩中的残留或者镁铁质岩石中的分异产物,均可形成Ap-Op... 详细信息

南极拉斯曼丘陵高级长英质变质岩中出现的磷灰石-斜方辉石(Ap-Opx)组合表明岩石经历了麻粒岩相条件下的变质作用,长英质片麻岩发生了强烈的脱水深熔作用。随着熔体的迁出,长英质片麻岩中的残留或者镁铁质岩石中的分异产物,均可形成Ap-Opx组合。残留矿物如磷灰石、金属氧化物等具有丰富的稀土元素,强烈影响着岩石中的稀土元素配分型式。磷灰石-斜方辉石组合的存在说明体系中有适量但不是很充足的有效钙质组分。由磷灰石、磁铁矿-钛铁矿、石榴石,直至斜方辉石,一方面反映了活动组分-残留组分的不断变化,另一方面,也说明高级变质作用过程中体系的失水程度逐渐增加;变质作用中富含该组合的岩石是经变质过程形成的特有岩石,没有固有的原岩可对应。

关键词：磷灰石斜方辉石深熔作用残留体组分活动南极

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周期性扩缩微通道接触冷凝流动及传热特性

化学工程 2021年第3期49卷 17-21页

作者：刘冬稔刘肖扬州大学机械工程学院江苏扬州225127

为了研究各参数对微通道流动及传热特性的影响,以水和水蒸气为工质,对周期性扩缩微通道接触冷凝流动及传热特性进行了实验研究。实验结果表明:周期性扩缩微通道内的主要流动形式为弹状流,在蒸气量不变的情况下,改变液相流量对流型的影... 详细信息

为了研究各参数对微通道流动及传热特性的影响,以水和水蒸气为工质,对周期性扩缩微通道接触冷凝流动及传热特性进行了实验研究。实验结果表明:周期性扩缩微通道内的主要流动形式为弹状流,在蒸气量不变的情况下,改变液相流量对流型的影响不大。由于周期性扩缩微通道能够有效打破流体的边界层,与直通道相比周期性扩缩微通道对传热有较大的强化作用,并且周期性扩缩微通道内流体的传热过程受流量的影响较大。此外,周期性扩缩微通道传热效果的提升以压力降的升高为代价,在实际应用中应平衡两者之间的关系,获得最佳效果。

关键词：膨胀-收缩传热微通道两相流

Investigation on Precipitation Hardening High Strength IF Steel Sheet for Automotive Application

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Journal of Iron and Steel Research International 2011年第S1期18卷 742-746页

作者： WANG Xu,liu ren-dong,WANG Ke-qiang,GUO Jin-yu,LIN Li,XU Rong-jie (Automobile and Home Appliance Steel Institute of Ansteel Company Limited Technology Centre,Anshan 114009,Liaoning,China) Ansteel Co Ltd Technol Ctr Automobile & Home Appliance Steel Inst Anshan 114009 Liaoning Peoples R China

High strength IF steel sheets with sufficient formability had been extensively used in automotive *** this paper,a new type of high strength cold-rolled IF steel with higher carbon and niobium contents was *** plastic and continuous annealing were performed on thermo-mechanical *** transformation points were tested by thermal expansion *** microscopy and transmission election microscope (TEM) were used to analyze the microstructure and the secondary precipitates of the *** results showed,the ductibility temperature range was from 950℃ to 1250℃ and the transformation points were 887℃ and 913℃ *** grain size of this steel was smaller than that of conventional high strength IF *** the mean time,there were many fine Nb(C,N) precipitates distributed in the intra-granular regions and the PFZ (precipitate free zone) were formed in the neighborhood of grain *** to the unique micro-structural feature,the yield strength and the yield ratio of the steel were decreased while the tensile strength was *** the increasing of the annealing temperature,the strength decreased,the total elongation A50,r-value at 15% strain and n-value were all *** order to obtain the favorable mechanical properties,the skin-pass rolling rate should be chosen at 0.6-0.8%.

关键词： high strength IF steel precipitation hardening grain refinement precipitate free zone (PFZ)

Evolution of microstructures in a nanotwinned steel investigated by nanoindentation and electrical resistivity measurement

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Evolution of microstructures in a nanotwinned steel investig...

“第十届中国钢铁年会”暨“第六届宝钢学术年会”

作者： ZHOU Peng liu ren-dong WANG Xu HUANG Ming-xin Department of Mechanical Engineering The University of Hong Kong Iron and Steel Research Institute Ansteel Group

A twinning-induced plasticity（TWIP）steel was subjected to cold rolling followed by recovery heat treatment,forming a nanotwinned *** the recovery annealing,the nanotwins are thermally stable so that they remain in the sample after recovery *** the contrary,the dislocation density was reduced greatly after recovery *** nanotwinned steel possesses a high yield strength,high ultimate tensile strength and good *** nanohardness tests and electrical resistivity measurements illustrate that the dislocation density increases dramatically in the nanotwinned steel during the tensile test while the twin volume fraction remains *** transmission electron microscopy（TEM）observation confirms the results from nanoindentation and electrical resistivity *** maximum volume fraction of deformation twins has been reached during the heavy cold rolling so that no more new deformation twins can be generated in the nanotwinned steel during tensile ***,the work hardening behaviour of the nanotwinned steel is mainly provided by the accumulation of dislocations.

关键词： Nanotwinned steel TWIP steel Nanotwins Nanoindentation Electrical resistivity

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南极中山站区高级片麻岩中蠕英石的形成

中国地质 2006年第6期33卷 1226-1235页

作者：任留东韩景仪中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所北京100037

南极中山站区(拉斯曼丘陵)高级片麻岩中多发育蠕英石即斜长石+石英,蠕英石的出现表明岩石中往往同时存在斜长石和钾长石。通常还有一些相关现象与蠕英石相伴,如矿物颗粒周围的斜长石±石英边、钾长石边。蠕英斜长石比主斜长石牌号更高... 详细信息

南极中山站区(拉斯曼丘陵)高级片麻岩中多发育蠕英石即斜长石+石英,蠕英石的出现表明岩石中往往同时存在斜长石和钾长石。通常还有一些相关现象与蠕英石相伴,如矿物颗粒周围的斜长石±石英边、钾长石边。蠕英斜长石比主斜长石牌号更高和更低的现象均可发生,而且蠕英斜长石的成分比主斜长石变化范围更大。蠕英石的形成主要涉及长英质矿物的变化,不仅涉及到钾长石的分解,可能还与钾长石的出溶、石英、黑云母的分解,甚至斜长石的出溶和分解有关。析出的组分对先存矿物(主要是钾长石)溶蚀和交代,同时出现蠕英石。变形有利于蠕英石的形成,但不是必要条件,长英质岩石中蠕英石的形成意味着降压过程的发生。形成蠕英石的组分主要源于体系自身,而不是外部环境。结合与相关结构的对比和分析,蠕英石的产生主要是长英质组分晚期分异的结果:由于K,Na(Ca)的分异,Na(Ca)^((2)+)沉淀,K^+组分活动,SiO_2亦可有一定的迁移;释放、迁移的组分更偏碱性。这种分异是岩石内部的成分和结构调整的产物,但相关组分活动的空间非常有限,一般限于若干个矿物颗粒的尺度。蠕英斜长石的形成可能代表着斜长石-石英之间的一种共结,并对新生斜长石的成分起到一种缓冲作用,其过程更接近溶液而不是岩浆性质,同时表示除H_2O外各种组分活动的基本结束。

关键词：蠕英石形成机制组分活动南极拉斯曼丘陵