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Baosteel Technical Research 2023年第1期17卷 32-38页

作者： zhang hanlong JIN Xinyan zhang Yulong Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China State Key Laboratory of Development and Application Technology of Automotive Steels(Baosteel) Shanghai201999China

Bainite, the main microstructure of ultrahigh-strength complex-phase(CP) sheet steel, usually exhibits various micro-morphologies when subjected to different austempering *** the current study, conventional austempering treatment at the bainite nose temperature resulted in two bainite types with distinct micro-morphologies: polygonal blocky bainite and acicular bainite, which resulted in large fluctuations in the mechanical properties of CP steel, particularly yield strength and hole expansion ***, the precise control of bainite micro-morphology was studied and applied to separate the two bainite types through austempering *** two bainite types of different micro-morphologies had different effects on the mechanical properties of CP steel: the acicular bainite favored hole expansion and flangeability but deteriorated ductility, while the polygonal blocky bainite favored ductility but deteriorated hole expansion and ***, two types of ultrahigh-strength CP steels of different mechanical properties can be stably manufactured through the precise control of bainitic micro-morphology to satisfy the specific demands of vehicle components in terms of the mechanical properties of CP steels.

关键词： UHSS microstructure control austempering bainite:

Influence of heat treatment processing on the microstructure and properties in medium manganese steel

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Baosteel Technical Research 2023年第1期17卷 17-21页

作者： zhang Yulong zhang hanlong WANG Li Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China State Key Laboratory of Development and Application Technology of Automotive Steels(Baosteel) Shanghai201999China

For the purpose of developing a 1 500 MPa grade steel sheet with excellent strength and ductility, a 0.15C-10Mn-1.5Al steel was employed to study austenite stability and microstructural evolution based on a novel double annealing *** a conventional intercritical annealing process, the sample was heated again to a temperature higher than A_(c3) for a very short time to generate austenite grains with different manganese content;thus, the microstructure of martensite plus austenite can be obtained at room *** experimental results show that with increasing annealing temperature, the tensile strength and yield strength *** the annealing temperature was higher than 820 ℃,the microstructure consisted of martensite plus austenite, and the tensile strength almost remained invariant with the annealing temperature.A tensile strength of 1 537 MPa and an elong-ation of 25.1% were achieved for the 820 ℃ *** volume fractions of austenite and martensite were identified by X-ray *** was found that with increasing annealing temperature, the volume fraction of the retained austenite decreased, and the ductility also had a gradual downward *** related austenite stability was discussed here as well.

关键词： medium Mn steel cold-rolled austenite martensite

Effects of quenching and over-aging temperatures on mechanical properties of ultra-high strength cold-rolled martensite steels

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Baosteel Technical Research 2019年第1期13卷 1-8页

作者： zhang hanlong ZHU Xiaodong XUE Peng Research Institute Baoshan Iron & Steel Co.Ltd. State Key Laboratory of Development and Application Technology of Automotive Steels( Baosteel)

As cold-formed steel has the highest strength-to-weight ratio of any material,ultra-high strength martensitic steel is attracting great interest from global car manufacturers. This paper explores the effects of the quenching and over-aging temperatures on the strength and cold bendability of C-Mn-Si martensitic steel. Due to its high carbon content,water-quenched C-Mn-Si martensitic steel has high hardenability and can obtain ultra-high tensile strength and uniform martensitic morphology when the water-quenching temperature is higher than 710 ℃.Increasing the over-aging temperature of this experimental steel decreases its tensile strength,increases the total elongation,and first increases then decreases the yield point until reaching a peak at 180 ℃. Besides,when increasing the over-aging temperature,the bendability of this experimental steel initially improves and then decreases,and reaches its optimal bendability at an over-aging temperature of 180 ℃. Based on SEM characterization and a microhardness distribution analysis,the over-aging temperatures were found to affect the size of the carbides and differences in the microhardness of the experimental steel. Therefore,they have significant influence on bendability.

关键词： martensitic steel annealing bendability

Study on the bendability and toughness of a 1 500 MPa cold-rolled martensitic sheet steel

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Baosteel Technical Research 2016年第3期10卷 28-34页

作者： ZHU Xiaodong XUE Peng LI Wei zhang hanlong Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201900China State Key Laboratory of Development and Application Technology of Automotive Steels(Baosteel) Shanghai 201900China

Cold rolled martensitic sheet steels are achieving more and more applications in car-making because of their ultra-high strength and potential for weight reduction. The relatively low plasticity of ultra-high strength martensitic steels might be a drawback for the applications in the aspects of forming and safety protection function and should be significantly noted. A 1 500 MPa grade cold rolled martensitic sheet steel has been studied to investigate the bendability at 90 degree bending and impact toughness as well as fracture surface morphology at various temperatures. Some discussions have been made basing upon the experiment data to get some understanding on the performance of the materials under various conditions and on how to make use of this kind of ultra high strength steel properly.

关键词： cold rolled martensitic steel sheet bendability toughness

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如何修复挖掘机上烧损的步进电机驱动模块

工程机械 2005年第11期36卷 68-69页

作者：章汉龙安徽太湖县小池镇百鸣村毛安小学 246440

在日立EX200型挖掘机及神钢SK200型挖掘机中都采用SS2B003驱动模块来驱动油门步进电机,由于线路外部老化短路引起模块烧坏的情况屡见不鲜,一般情况都采取换整块新电脑板的办法,花费极大,实际损坏的只是SS2B003小模块当中的驱动功率晶体... 详细信息

在日立EX200型挖掘机及神钢SK200型挖掘机中都采用SS2B003驱动模块来驱动油门步进电机,由于线路外部老化短路引起模块烧坏的情况屡见不鲜,一般情况都采取换整块新电脑板的办法,花费极大,实际损坏的只是SS2B003小模块当中的驱动功率晶体管,只要搞清内部结构,将损坏的功率管换上新的功率管就可以恢复工作,花费极少.

关键词：挖掘机挖掘机械步进电机驱动模块

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基于模板检测的违法网站识别方法

南京理工大学学报 2015年第3期39卷 266-271页

作者：张瀚珑沈备军王永剑上海交通大学软件学院上海200240 公安部第三研究所上海200031

为高效识别违法网站,该文提出了一种新方法。从HTTP POST提取特征值,计算网站间相似度,对网站进行聚类并抽取违法网站模板用来识别违法网站。应用图挖掘技术过滤合法网站,提升识别效率。以赌博网站为例,在真实环境中对该方法进行了大规... 详细信息

为高效识别违法网站,该文提出了一种新方法。从HTTP POST提取特征值,计算网站间相似度,对网站进行聚类并抽取违法网站模板用来识别违法网站。应用图挖掘技术过滤合法网站,提升识别效率。以赌博网站为例,在真实环境中对该方法进行了大规模实验和评估。实验结果表明:该方法检测出赌博网站的精确度为1;与URL、HTML和语义特征相比,HTTP POST特征值的F-Measure最好;应用图挖掘技术可以有效过滤合法网站,提高整个流程运行效率20%。

关键词：模板检测违法网站识别相似度聚类图挖掘赌博网站

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东西汇双塔高位大跨度斜交连体结构设计

建筑结构 2022年第17期52卷 78-84页

作者：杨坚杨坤张汉龙广州珠江外资建筑设计院有限公司广州510060

东西汇连体双塔的塔楼高度分别为119、167.3m,高位连接体跨度约70m,塔楼与塔楼之间及塔楼与连接体之间的主抗侧力角度均有夹角,为高位大跨度斜交连体超限结构。主体双塔分别采用框架-剪力墙结构体系、框架-核心筒结构体系,连接体为钢桁... 详细信息

东西汇连体双塔的塔楼高度分别为119、167.3m,高位连接体跨度约70m,塔楼与塔楼之间及塔楼与连接体之间的主抗侧力角度均有夹角,为高位大跨度斜交连体超限结构。主体双塔分别采用框架-剪力墙结构体系、框架-核心筒结构体系,连接体为钢桁架体系。根据结构的超限情况合理选取抗震性能化设计目标,详细论述了连接体对两塔楼动力特性的影响,对超长钢结构连接体进行温度应力分析、抗连续倒塌分析、竖向振动舒适度分析、施工模拟分析并且介绍了连接体关键节点的设计。根据结构特点采取了有针对性的加强措施。结果表明,各项指标均良好,结构能实现设定的抗震性能目标。

关键词：超限高层结构复杂连体结构竖向振动舒适度抗连续倒塌分析

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珠海某超限高层建筑的性能分析与设计

建筑结构 2024年第11期54卷 24-30页

作者：杨坚杨坤张汉龙广州珠江外资建筑设计院有限公司广州510060

中葡商贸中心南侧塔楼为B级高度高层建筑,采用钢筋混凝土框架-核心筒结构体系,结构同时存在扭转不规则、楼板不连续、局部穿层柱及斜柱等不规则项。根据结构的超限情况合理选取抗震性能化设计目标,采用PKPM和MIDAS Building两款程序对... 详细信息

中葡商贸中心南侧塔楼为B级高度高层建筑,采用钢筋混凝土框架-核心筒结构体系,结构同时存在扭转不规则、楼板不连续、局部穿层柱及斜柱等不规则项。根据结构的超限情况合理选取抗震性能化设计目标,采用PKPM和MIDAS Building两款程序对整体结构进行了小震下弹性反应谱和弹性时程分析,补充了中震弹性和不屈服验算,并采用SAUSAGE程序进行了罕遇地震下的弹塑性动力时程分析。针对楼板不连续、局部穿层柱和斜柱等不规则情况还进行了楼板应力分析、屈曲稳定分析以及斜柱转折处的受力分析。根据结构特点采取了相应的加强措施。分析结果表明,各项指标均表现良好,结构各项性能均能达到预定的抗震性能目标,结构体系合理可行。

关键词：超限高层性能设计时程分析穿层柱分析

基于Al-Ti-B细化剂的铝合金异质形核机制研究进展

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中国材料进展 2018年第8期37卷 632-637页

作者：韩延峰张瀚龙徐钧张佼孙宝德上海交通大学材料科学与工程学院上海200240 上海交通大学上海市先进高温材料及其精密成形重点实验室上海200240 上海交通大学金属基复合材料国家重点实验室上海200240

综述了Al-Ti-B中间合金细化铝合金的现有理论、假说以及发展趋势,分析了现有异质形核模型的不足。形核相在异质核心上的形核属于液-固相变,熔体与固相质点接触的液/固界面区微结构决定着异质形核过程。从液-固相变角度出发,研究熔体与... 详细信息

综述了Al-Ti-B中间合金细化铝合金的现有理论、假说以及发展趋势,分析了现有异质形核模型的不足。形核相在异质核心上的形核属于液-固相变,熔体与固相质点接触的液/固界面区微结构决定着异质形核过程。从液-固相变角度出发,研究熔体与异质质点间液/固界面区熔体原子有序结构形成及其在随后异质形核过程中的演变规律,将比固-固晶格匹配的唯象分析方法更直接、更真实地反映异质形核的物理过程,据此对异质核心诱导形核相形核的能力进行判定将更为有效。

关键词：铝合金凝固异质形核晶粒细化液/固界面

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广州某会议中心的结构分析与设计

广东土木与建筑 2024年第10期31卷 15-18页

作者：张汉龙广州珠江外资建筑设计院有限公司广州510060

广州某会议中心建筑外观造型独特,整体结构复杂。根据结构受力特点,常规跨度楼盖区域采用普通钢筋混凝土构件支承,而跨度较大楼盖区域则采用钢梁+型钢混凝土柱+钢筋桁架楼承板的结构形式。结构整体分析指标表现良好,说明结构布置合理;... 详细信息

广州某会议中心建筑外观造型独特,整体结构复杂。根据结构受力特点,常规跨度楼盖区域采用普通钢筋混凝土构件支承,而跨度较大楼盖区域则采用钢梁+型钢混凝土柱+钢筋桁架楼承板的结构形式。结构整体分析指标表现良好,说明结构布置合理;二层超长楼盖在温度作用组合工况下的应力均未超过混凝土抗拉强度标准值,楼板在正常使用状态下未出现开裂。另外,还补充了项目北侧大跨度弧形钢连廊的构件应力分析、变形验算以及竖向振动舒适度验算,分析结果表明大跨度连廊结构竖向振动舒适度满足要求且具有足够的承载力和刚度。

关键词：动力特性大跨度钢结构变形验算舒适度分析