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Fatigue Strength Improvement of Welded Joint by Ultrasonic Peening in Ultra-Fine Grain Steel

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Journal of Iron and Steel Research International 2003年第3期10卷 64-66页

作者： tian zhi-ling ZOU Gang HE Chang-hong ZHANG Xiao-mu Central Iron and Steel Research Institute

The influence of rare earths (RE) on carbides in high carbon steel weld metal was studied by transmission electron microscope (TEM) and energy dispersive X ray microanalysis (EDX). It is found that rare earth markedly affects the quantity, morphology and distribution of carbides. The precipitating mechanism of carbides was proposed in which rare earth compounds with high surface energy serve as the nucleation sites for carbides in superheated liquid metal and the induced carbides are precipitated extensively and distributed evenly. The preferential precipitation of carbides decreases the carbon content in matrix, which is transformed into low carbon lath martensite after welds are chilled to room temperature.

关键词： rare earth metal carbide weld

Wear Evaluation on Ni_3Al/MnS Composite Related to Metallurgical Processes

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Journal of Iron and Steel Research International 2012年第7期19卷 46-54页

作者： Karin Gong LUO He-li ZHOU zhi-feng tian zhi-ling Lars Nyborg LI Chang-hai Department of Materials and Manufacturing Technology Chalmers University of Technology Gothenburg Se-412 96 Sweden China Iron and Steel Research Institute Group Beijing 100081 China Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Hong Kong China

Iron alloyed Ni3Al with composition of Ni-18. 8Ab10. 7Fe-0. 5Mn-0. 5Ti-0. 2B in atom percent （NAC alloy） showed attractive tribological properties under unlubrication condition at room temperature. The alloy was prepared by hot isostatic pressing （HIP） process. The wear properties were associated with its intrinsic deformation mechanism. Unfortunately, the single phase NAC-alloy worked inadequately with its counterpart disk, and also showed a poor machinability. In the present work, NAC-alloy matrix composite with 6 % （volume percent） MnS particle addi- tion was studied to improve its wear behaviors and performance on machining. Two metallurgical processes of HIP and vacuum casting were applied to produce the testing materials. Pin-on-disk （POD） measurements were carried out at room temperature. A commercial vermicular graphite cast iron was selected as a reference material. The counter- part disk was made of a grey cast iron as liner material in ship engines. The contact pressures of 2.83 MPa and 5.66 MPa were normally applied in the tests. The investigation indicated that MnS particle addition in the NAC-alloy composites functions as an effective solid lubricant, and improved wear properties and machinability of the materials. Obvi- ously, as-cast NAC-alloy with in-situ formed MnS-phase was working more effectively with the counterpart, compa- ring to the HIPed NAC-alloy composite with MnS particles. At the high contact pressure of 5.66 MPa, the specific wear rate of the as-cast NAC-alloy composite was high. The phenomenon of the negative effect is mostly due to the brittle second NiAl phase as evidenced in the microstructure analysis.

关键词： HIP processing friction coefficient specific wear rate intermetallics sliding wear casting machinability

Mathematical Model of Microstructure Evolution of X60 Line Pipe Steel During CSP Hot Rolling

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Journal of Iron and Steel Research International 2010年第1期17卷 70-78页

作者： Li Quan LIU Zheng-dong TANG Guang-bo tian zhi-ling Siciliano Fulio Institute for Structural Materials Central Iron and Steel Research Institute Beijing 100081 China Company Brazil Metallurgy and Mineral R. Pequetita 111 04552-902 Sao Paulo Brazil

An integrated process modelling system for simulating the microstructure evolution of Nb-microalloyed HSLA steel produced in CSP hot rolling process has been developed on the basis of the microstructure simulation and mechanical properties prediction technology. 3-D thermomechanical coupled finite element models for simulating hot strip rolling have been developed and the distribution of equivalent plastic strain through the thickness direction of the rolled material by CSP rolling was obtained. Thus the distribution of temperature, strain and strain rate through the thickness of the steel stocks, as well as the microstructure evolution during hot rolling of X60 line pipe steel strip has been investigated by using the developed integrated process modelling system. In addition, the determination and optimization of controllable process parameters during CSP hot strip rolling for the Nb-microalloyed X60 line pipe steel have been implemented, and control strategies such as adopting larger pass reduction in the first stand, arranging appropriate pass interval times and proper rolling speed, to reduce or eliminate mixed grain microstructure of Nb microalloyed strip in CSP processing have been proposed.

关键词： CSP line pipe steel niobium microalloying microstructure evolution mathematical modelling

Electrocatalytic behaviors of poly acridine orange/multi-walled carbon nanotube modified electrode

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Journal of Chemistry and Chemical Engineering 2008年第6期2卷 44-48页

作者： WANG Zong-hua XIA Yan-zhi tian ling ZHANG Fei-fei Laboratory of Fiber Materials and Modern Textile the Growing Base for State Key Laboratory Qingdao University Qingdao 266071 China

In this work, noncovalent functionalization of multiwalled carbon nanotube （MWNT） with acridine orange （AO） by electropolymerization is studied. The obtained composite film is a viable alternate electrode material, non-toxic, chemical inert, not volatile, using to construct modified electrode. The new type modified electrode has both of unique properties of MWNT and poly acridine orange （POAO）, can provide good sensitivity, low limits of detection, good response precision, and superb response stability.

关键词： multi-walled carbon nanotube acridine orange modified electrode

选区熔化3D打印TiAl基合金的研究现状及展望

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表面技术 2021年第1期50卷 173-186页

作者：王虎彭云赵琳田志凌钢铁研究总院先进钢铁流程及材料国家重点实验室北京100081 北华航天工业学院材料工程学院河北廊坊065000

TiAl基合金(TiAl基金属间化合物),被认为是一种理想的新型轻质高温结构材料,在当代民用工业、兵器工业以及航空航天等领域具有广阔的应用前景。然而TiAl基合金脆性较大,传统的成形方法难以制备出复杂结构的构件,严重制约了该合金的推广... 详细信息

TiAl基合金(TiAl基金属间化合物),被认为是一种理想的新型轻质高温结构材料,在当代民用工业、兵器工业以及航空航天等领域具有广阔的应用前景。然而TiAl基合金脆性较大,传统的成形方法难以制备出复杂结构的构件,严重制约了该合金的推广与应用。选区熔化3D打印是按照CAD模型的分层切片数据,以激光或者电子束为高能量热源逐层扫描熔化粉末,逐层堆积,直接实现构件的制造,代表了TiAl基合金成形最前沿、最新颖的技术。基于激光选区熔化成形(SLM)与电子束选区熔化成形(SEBM)制备TiAl基合金的最新研究成果,重点归纳了成形过程中常见缺陷的形成原因以及控制措施,详细阐述了工艺参数对成形质量、微观组织以及力学性能的影响规律,然后对比分析了SLM和SEBM制备TiAl基合金的优缺点。国内外的研究结果表明,控制TiAl合金的开裂倾向是SLM制备TiAl合金需要解决的首要问题,也是提高成形件致密度,改善力学性能的基础;而SEBM技术通过工艺优化,能够较好地抑制TiAl合金的开裂,获得高致密度成形件,其力学性能可以达到传统锻件、铸件的水平,更加适合TiAl合金的3D打印。最后对选区熔化3D打印TiAl基合金的研究方向提出了建议。

关键词： TiAl基合金 3D打印激光选区熔化成形电子束选区熔化成形冶金缺陷致密度 Al元素烧损微观组织

马氏体不锈钢的微观组织各向异性对微区应力和氢分布的影响

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材料工程 2016年第10期44卷 80-87页

作者：钟振前田志凌杨春钢铁研究总院分析测试所北京100081 清华大学材料学院北京100083

利用电子背散射衍射(EBSD)实验分析了马氏体组织的微区弹性刚度分布,并在此基础上建立应力-氢交互作用的耦合有限元模型,研究马氏体组织的各向异性对微区应力和氢分布的影响。结果表明:相邻Block板条束之间的取向差互成60°,在同一受力... 详细信息

利用电子背散射衍射(EBSD)实验分析了马氏体组织的微区弹性刚度分布,并在此基础上建立应力-氢交互作用的耦合有限元模型,研究马氏体组织的各向异性对微区应力和氢分布的影响。结果表明:相邻Block板条束之间的取向差互成60°,在同一受力方向上不同Block板条束具有不同的弹性刚度,从而引发组织间的微区应力和氢呈不均匀分布,Block板条束是表征微区应力的组织单元。Block板条束弹性刚度梯度和组织尺寸决定了组织间的应力集中,而应力集中又影响了氢的分布。弹性刚度梯度高和板条束尺寸大的Block组织单元应力集中较为严重,并富集高浓度的氢,最终引发氢致开裂。上述模拟结果与氢脆断口的微观断裂形貌和氢脆裂纹的EBSD分析结果相符。

关键词：各向异性氢扩散弹性刚度氢脆 FEM EBSD

EBSD技术在研究高强马氏体不锈钢氢脆机理中的应用

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材料热处理学报 2015年第2期36卷 77-83页

作者：钟振前田志凌杨春钢铁研究总院测试所北京100081 清华大学材料学院北京100083

用EBSD技术研究了在恒定应力和长期氢扩散作用下马氏体不锈钢的氢脆断裂机制。结果表明,氢脆在初期阶段萌生沿晶裂纹,晶界开裂有选择性和倾向性,高能量的大角晶界易发生开裂,低能量的CSL晶界抑制氢脆裂纹。沿晶裂纹两侧的塑性应变宽度... 详细信息

用EBSD技术研究了在恒定应力和长期氢扩散作用下马氏体不锈钢的氢脆断裂机制。结果表明,氢脆在初期阶段萌生沿晶裂纹,晶界开裂有选择性和倾向性,高能量的大角晶界易发生开裂,低能量的CSL晶界抑制氢脆裂纹。沿晶裂纹两侧的塑性应变宽度仅为微米或亚微米量级,宏观下表现出典型的脆性开裂特征。扩展阶段氢脆裂纹沿特定的滑移系和解理面穿晶扩展,穿越不同晶粒时,裂纹随解理或滑移晶面的取向变化而发生弯折。氢脆断裂机制符合结合力降低和氢促进局部塑性变形模型。

关键词：氢脆 EBSD 沿晶裂纹解理面滑移面

加碳条件下钼精矿真空冶炼过程中主要杂质元素的行为分析

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中国有色金属学报 2020年第2期30卷 438-446页

作者：王磊郭培民孔令兵赵沛田志凌钢研晟华科技股份有限公司北京100081 钢铁研究总院先进钢铁流程及材料国家重点实验室北京100081

采用在钼精矿真空冶炼过程中添加碳粉的方法,进一步降低钼精矿真空冶炼过程中主要杂质SiO2、MgO、Al2O3和CaO的含量。热力学计算结果表明:SiO2、MgO、Al2O3和CaO均有可能与碳发生反应,生成气态物质被去除。试验研究结果表明,在钼精矿真... 详细信息

采用在钼精矿真空冶炼过程中添加碳粉的方法,进一步降低钼精矿真空冶炼过程中主要杂质SiO2、MgO、Al2O3和CaO的含量。热力学计算结果表明:SiO2、MgO、Al2O3和CaO均有可能与碳发生反应,生成气态物质被去除。试验研究结果表明,在钼精矿真空冶炼过程中加入碳粉可以明显降低其中Si、Mg、Al和Ca的含量,其中Si的脱除率约达到100%,Mg的脱除率约达到99.7%,Al的脱除率约达到78.44%,Ca的脱除率最高约为9.8%。采用品位为48%的低品位钼精矿为原料,经过真空冶炼过程,得到的金属钼产品中钼含量达到92%,S含量降至0.69%,主要杂质元素SiO2含量降至0.0021%,Cu含量小于0.005%,P含量小于0.005%,Mg含量降至0.001%,Al含量降至0.64%,Ca含量为0.51%。

关键词：钼精矿碳真空冶炼杂质元素金属钼产品

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Ti对大线能量焊接焊缝组织和性能的影响

钢铁研究学报 2014年第6期26卷 47-53页

作者：阿荣潘川赵琳田志凌安泰科技股份有限公司焊接材料分公司北京100081 新冶高科技集团有限公司北京100081 中国钢研科技集团有限公司北京100081

对不同Ti含量的气电立焊焊缝组织及力学性能进行了对比研究。结果表明,Ti的质量分数在0.028%~0.038%范围内时,焊缝中获得大量细小的针状铁素体,焊缝组织及低温韧性得以明显改善。当Ti过量时,焊缝中的针状铁素体减少,组织以贝氏体为主,... 详细信息

对不同Ti含量的气电立焊焊缝组织及力学性能进行了对比研究。结果表明,Ti的质量分数在0.028%~0.038%范围内时,焊缝中获得大量细小的针状铁素体,焊缝组织及低温韧性得以明显改善。当Ti过量时,焊缝中的针状铁素体减少,组织以贝氏体为主,低温韧性相应下降。焊缝组织中观察到块状和条状的M-A组元,随着焊缝Ti含量增加,其总量增加。焊缝夹杂物多为以氧化物为核心,外层包裹着MnS的复合夹杂物,并随夹杂物Ti含量的增加,由Mn-Si-Al-O型向Ti-Mn-Al-O型转变,有利于促进针状铁素体形成。而当焊缝中Ti过量时,主要夹杂物又转变为对针状铁素体形核无效的Ti-Al-O型,促进了贝氏体转变。

关键词：大线能量焊接 Ti 针状铁素体 M-A组元焊缝组织力学性能