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配置600MPa钢筋的预应力混凝土梁受弯性能研究 Experimental research on bending behavior of prestressed concrete beams with 600MPa steel bars  [PDF]
戎贤,吴海超,刘平
- , 2018,
Abstract: 为研究配置600 MPa级高强钢筋有粘结部分预应力混凝土梁的受弯性能,在静力荷载作用下,进行了9根纵向受拉非预应力筋采用600 MPa级高强钢筋的试验梁受弯性能试验.对比分析试验梁的破坏特征、受力过程、受弯承载力、挠度等.研究结果表明:配置600 MPa级高强钢筋的后张法有粘结部分预应力混凝土梁和配置普通钢筋后张法有粘结部分预应力混凝土梁的受力性能相同;配置600 MPa级高强钢筋的试验梁的受弯承载力可以按照现行《混凝土结构设计规范》中相关公式计算.当600 MPa级高强钢筋取520 MPa的强度设计值时,采用现行规范计算配置600 MPa级高强钢筋的试验梁受弯承载力的安全储备较高
配置600 MPa级高强钢筋T形柱抗震性能试验研究
Experimental analysis of seismic behavior of 600 MPa RC T-shaped columns
 [PDF]

戎贤,段微微,王浩
- , 2017, DOI: 10.11835/j.issn.1674-4764.2017.02.019
Abstract: 600 MPa级钢筋是一种新型高强度钢筋,为研究该钢筋应用于异形柱结构体系的可行性,对7根不同轴压比、体积配箍率和钢筋强度的混凝土T形柱试件进行低周往复荷载试验,分别对其承载力、位移、滞回曲线、骨架曲线、刚度退化和耗能性能进行研究,综合评估其抗震性能。研究结果表明:配置600 MPa级钢筋的混凝土T形柱具有良好的变形能力和承载能力,提高配箍率能有效提高试件的抗震性能,提高轴压比可以提高试件的承载力,但降低其变形能力。随着钢筋强度的提高,试件的承载力显著提高。
600 MPa steel bar was a new type of high-strength reinforcing bar. Seven T-shaped column specimens varying in stirrup ratios, axial compression ratios and steel strength were tested under low cyclic loading to investigate the feasibility of using this type of reinforcement in specially shaped column. Behaviors in bearing capacity, displacement, hysteretic behavior, skeleton characteristic, rigidity degradation and energy dissipation were investigated to analysis the seismic performance of columns. The results showed that 600 MPa RC T-shaped columns had favorable deformation capacity and bearing capacity. Improving stirrup ratios could effectively improve the seismic performance. With the increase of axial compression ratios, the bearing capacity of columns was bigger, but the deformation capacity deteriorated. With the improvement of the strength of steel, bearing capacity, deformation capacity significantly increased.
TSCR工艺制备600MPa级TRIP钢的组织与力学性能  [PDF]
张迎晖,赵鸿金,康永林
材料工程 , 2009,
Abstract: 在实验室条件下模拟薄板坯连铸连轧工艺试制了600MPa级C-Si-Mn系TRIP钢,拉伸实验检测表明,试验钢的力学性能为σb=630MPa,σs=460MPa,δ=29.1%;组织观察发现,试样组织为铁素体+贝氏体+残余奥氏体,彩色金相定量分析结果表明残余奥氏体的体积分数为6.6%。
Effects of overaging temperature on the microstructure and properties of 600 MPa cold-rolled dual-phase steel  [PDF]
Chun-fu Kuang,Zhi-wang Zheng,Gong-ting Zhang,Jun Chang,Shen-gen Zhang,Bo Liu
- , 2016, DOI: https://doi.org/10.1007/s12613-016-1310-4
Abstract: C–Mn steels prepared by annealing at 800°C for 120 s and overaging at 250–400°C were subjected to pre-straining (2%) and baking treatments (170°C for 20 min) to measure their bake-hardening (BH2) values. The effects of overaging temperature on the microstructure, mechanical properties, and BH2 behavior of 600 MPa cold-rolled dual-phase (DP) steel were investigated by optical microscopy, scanning electron microscopy, and tensile tests. The results indicated that the martensite morphology exhibited less variation when the DP steel was overaged at 250–350°C. However, when the DP steel was overaged at 400°C, numerous non-martensite and carbide particles formed and yield-point elongation was observed in the tensile curve. When the overaging temperature was increased from 250 to 400°C, the yield strength increased from 272 to 317 MPa, the tensile strength decreased from 643 to 574 MPa, and the elongation increased from 27.8% to 30.6%. Furthermore, with an increase in overaging temperature from 250 to 400°C, the BH2 value initially increases and then decreases. The maximum BH2 value of 83 MPa was observed for the specimen overaged at 350°C.
Kinetics and formation mechanisms of intragranular ferrite in V-N microalloyed 600 MPa high strength rebar steel  [PDF]
Jing Zhang,Fu-ming Wang,Chang-rong Li
- , 2016, DOI: https://doi.org/10.1007/s12613-016-1251-y
Abstract: To systematically investigate the kinetics and formation mechanisms of intragranular ferrite (IGF), isothermal heat treatment in the temperature range of 450°C to 600°C with holding for 30 s to 300 s, analysis of the corresponding microstructures, and observation of the precipitated particles were conducted in V-N microalloyed 600 MPa high strength rebar steel. The potency of V(C,N) for IGF nucleation was also analyzed statistically. The results show that the dominant microstructure transforms from bainite (B) and acicular ferrite (AF) to grain boundary ferrite (GBF), intragranular polygonal ferrite (IPF), and pearlite (P) as the isothermal temperature increases from 450°C to 600°C. When the holding time at 600°C is extended from 30 s to 60 s, 120 s, and 300 s, the GBF content ranges from 6.0vol% to 6.5vol% and the IPF content increases from 0.5vol% to 2.8vol%, 13.1vol%, and 13.5vol%, respectively, because the ferrite transformation preferentially occurs at the grain boundaries and then occurs at the austenite grains. Notably, V(C,N) particles are the most effective nucleation site for the formation of IPF, accounting for 51% of the said formation.
配置600MPa级钢筋部分预应力混凝土梁受力性能 Mechanical performance of partially prestressed concrete beams with 600MPa steel bar  [PDF]
李艳艳,李晓清
- , 2018,
Abstract: 通过进行12根有粘结部分预应力、无粘结部分预应力高强钢筋混凝土梁的试验研究,对比分析混凝土强度等级、预应力筋和非预应力纵向受拉钢筋配筋率对2种部分预应力高强钢筋混凝土梁受弯承载力、挠度及刚度的影响.研究结果表明:增加预应力筋和非预应力筋配筋率能够显著提高有粘结部分预应力、无粘结部分预应力高强钢筋混凝土梁的受弯承载力,减缓试验梁的刚度退化.有粘结、无粘结部分预应力高强钢筋混凝土梁的受弯承载力可以按照现行《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTG D62-2004)中相关公式计算.当600MPa级钢筋抗拉强度的设计值取500 MPa时,按规范计算梁受弯承载力具有足够的安全储备
600MPa级高强韧耐海洋大气腐蚀钢的相变规律研究  [PDF]
王建泽,康永林,杨善武,周建
材料工程 , 2007,
Abstract: 利用Gleeble-1500热/力模拟实验机,研究了新开发的屈服强度600MPa级高强韧耐海洋大气腐蚀钢的相变规律,分析了不同冷却速率对钢组织的影响。结果表明新开发钢相变开始温度550~650℃,终了相变温度440~530℃;连续冷却转变的显微组织随冷速的增加形态多变。
600 MPa级元宝梁用钢冲压开裂原因分析  [PDF]
惠亚军,宁林新,潘辉,刘锟,李文远,王智权
- , 2018, DOI: 10.11951/j.issn.1005-0299.20170056
Abstract: 为解决元宝梁冲压开裂问题,用OM和SEM等仪器与ABAQUS有限元仿真软件对600 MPa级元宝梁用钢冲压开裂原因进行了分析.结果表明:600 MPa级元宝梁用钢化学成分、力学性能与冷弯性能均满足标准要求,金相组织为准多边形铁素体与少量珠光体的混合组织,不存在带状组织;开裂件断口形貌呈现出明显鱼骨状形貌,钢板中心分层,两侧分布起源于中心分层并沿同一方向扩展的三角形台阶状断口,不同形貌断口均属于韧性断裂,而断口整体形貌显示材料在断裂前没有发生缩颈过程.利用ABAQUS软件对“先冲压再压边工艺”与“先压边再冲压工艺”两种工况进行有限元分析,结果显示:先冲压再压边工艺边部应力集中更严重,边部节点应力超过了材料抗拉强度从而导致撕裂现象的发生;由“先冲压再压边工艺”改为“先压边再冲压工艺”后元宝梁冲压开裂率由50%降至0,材料边部变形均匀,未见缩颈与开裂现象发生.
In order to solve the problem of stamping cracking of crossbeam steel, the reasons of stamping cracking of 600 MPa grade crossbeam steel were revealed by using optical microscopy (OM), scanning electron microscopy (SEM) and ABAQUS finite element simulation software. The results show that the chemical composition, mechanical properties and cold bending properties of 600 MPa grade crossbeam steel can meet the standard requirements, and the microstructure is composed of pseudo-polygonal ferrite and a small amount of pearlite, without banded structure. The fracture surface showed a fishbone-like morphology. The center of the steel plate was stratified. The triangular step-like fracture originated from the central crack and distributed by the two sides which extended in the same direction. The fracture of different morphologies exhibited a ductile mode. The whole fracture morphology suggested that no necking occurred before fracture. Two kinds of stamping working conditions were simulated by ABAQUS software. The results showed that the process of first stamping and then blank pressing induced great stress concentration in the edge of plate, and the node stress of plate edge exceeded the tensile strength, leading to the tearing phenomenon. The cracking rate of crossbeam was reduced from 50% to 0 when the stamping process changed from first stamping and then blank pressing to first blank pressing and then stamping. At this moment the edge deformation of the material was uniform, without any shrinkage and cracking.
Effect of hot-dip galvanizing processes on the microstructure and mechanical properties of 600-MPa hot-dip galvanized dual-phase steel  [PDF]
Chun-fu Kuang,Zhi-wang Zheng,Min-li Wang,Quan Xu,Shen-gen Zhang
- , 2017, DOI: https://doi.org/10.1007/s12613-017-1530-2
Abstract: A C–Mn dual-phase steel was soaked at 800°C for 90 s and then either rapidly cooled to 450°C and held for 30 s (process A) or rapidly cooled to 350°C and then reheated to 450°C (process B) to simulate the hot-dip galvanizing process. The influence of the hot-dip galvanizing process on the microstructure and mechanical properties of 600-MPa hot-dip galvanized dual-phase steel (DP600) was investigated using optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and tensile tests. The results showed that, in the case of process A, the microstructure of DP600 was composed of ferrite, martensite, and a small amount of bainite. The granular bainite was formed in the hot-dip galvanizing stage, and martensite islands were formed in the final cooling stage after hot-dip galvanizing. By contrast, in the case of process B, the microstructure of the DP600 was composed of ferrite, martensite, bainite, and cementite. In addition, compared with the yield strength (YS) of the DP600 annealed by process A, that for the DP600 annealed by process B increased by approximately 50 MPa because of the tempering of the martensite formed during rapid cooling. The work-hardening coefficient (n value) of the DP600 steel annealed by process B clearly decreased because the increase of the YS affected the computation result for the n value. However, the ultimate tensile strength (UTS) and elongation (A80) of the DP600 annealed by process B exhibited less variation compared with those of the DP600 annealed by process A. Therefore, DP600 with excellent comprehensive mechanical properties (YS = 362 MPa, UTS = 638 MPa, A80 = 24.3%, n = 0.17) was obtained via process A.
基于屈服平台理论开发的600MPa级高强塑性螺纹钢的研究*  [PDF]
李小龙,郭正洪,戎咏华,吴海洋,姚圣法
金属学报 , 2014, DOI: 10.3724/SP.J.1037.2013.00768
Abstract: 采用冷轧与热处理相结合的方式研究了铁素体晶粒尺寸对力学性能的影响.将C含量为0.1%(质量分数)的板材经不同道次的冷轧,随后在600℃进行再结晶退火5~300min,获得晶粒直径在5.2~40.4μm之间的铁素体.室温拉伸实验结果表明,细化铁素体晶粒不仅提高了强度,还有效增加了屈服平台延伸率.SEM观察表明,细化晶粒促进了塑性形变在不同晶粒间的均匀性,宏观上累积成了较长的屈服平台.结合Hollomon和Hall-Petch公式导出屈服平台延伸率δL与晶粒尺寸dα之间存在的定量关系,并确定了公式的适用范围.采用狭缝喷水实现快速冷却的新方法对HRB400钢筋进行热处理,不仅获得细晶铁素体,而且得到高比例的非平衡珠光体,使材料在获得高强度的同时还具有相当的塑性,由此开发出具有明显的屈服平台的600MPa级高强塑性螺纹钢,该商业用钢的成功开发进一步印证了理论分析的正确性.
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