赵河山
,
李殿中
,
刘朝霞
,
李依依
金属学报
利用热模拟机Gleeble3500在温度Ae3~Ar3之间针对低碳钢进行形变诱导铁素体相变的实验研究，其应力-时间曲线表明形变诱导铁素体相变在很短时间内转变完全，C得不到充分扩散。利用电子探针对铁素体相C浓度的分析表明诱导铁素体相中C含量远高于常规铁素体中C含量。扫描电子显微镜对形变试样的研究表明，由于C含量的过饱和导致诱导铁素体相是一种非稳定状态的过渡相，在回火过程中，诱导铁素体相将会排出内部过饱和的C并最终向稳定存在的铁素体相转变，其硬度随之降低。
关键词:
形变诱导铁素体
,
low carbon steel
,
null
,
null
刘光洲王建明张鉴清曹楚南
金属学报
doi:10.3724/SP.J.1037.2010.00239
采用开路电位-时间和电化学阻抗谱等测量方法, 研究了3.5%NaCl水溶液中总余氯(TRC)含量对船用低碳钢Q235腐蚀行为的影响. 结果表明, 舱体金属腐蚀可以分为表面迅速氧化, 表面形成氧化物覆盖层, 覆盖层发生破损导致腐蚀3个阶段. TRC含量较低 (如5和10 mg/L)时, 压载舱壁金属的腐蚀略有增强. 而当TRC含量较高时(如20 mg/L), 则可以促进舱体金属表面钝化并形成致密腐蚀产物而堵塞氧化物覆盖层的破损, 致使舱体金属的开路电位提高, 电荷传递电阻增加, 使舱体金属的抗腐蚀能力增强. 电解法压载水处理在杀灭水生生物的同时对于压载舱壁金属腐蚀而言是安全的, 且较高的TRC含量在提高杀灭效率、缩短杀灭时间的同时, 并不会导致严重的舱壁金属腐蚀.
关键词:
压载水
,
electrolytic treatment
,
low carbon steel
,
corrosion
,
electrochemical method
阳靖峰董俊华柯伟陈楠
金属学报
doi:10.3724/SP.J.1037.2010.00439
研究了在pH值分别为8, 9和10的除氧硼酸缓冲溶液中, 低碳钢腐蚀产物对其活化/钝化敏感性的影响. 实验结果表明, 在pH值为8时, 低碳钢一直处于活性溶解状态, 不受腐蚀产物影响; 在pH值为9和10时, 表面腐蚀产物使低碳钢钝化, 其腐蚀电位最后稳定于钝化区间. XPS和XRD等分析结果表明, 腐蚀产物由Fe6(OH)12B4O7和γ-FeOOH组成. 腐蚀产物覆盖的低碳钢比裸低碳钢更容易发生钝化.
关键词:
硼酸缓冲溶液
,
low carbon steel
,
corrosion product
,
active/passive
,
potentiostat preparation
张安峰
,
王豫跃
,
邢建东
,
李长久
金属学报
用失重法和电化学法系统地研究了20钢基体、两种Ni基涂层(Ni60JH和Delelo50) 以及对比材料1Cr18Ni9Ti不锈钢在液/固两相流(5%H2SO4+15%石英砂) 中冲刷与腐蚀的交互作用. 实验表明: (1) 在冲刷速率为5---10 m/s时, Ni60JH涂层的耐冲刷腐蚀性能比基体高8---15倍多, 并优于1Cr18Ni9Ti不锈钢;
Delelo50涂层的耐冲刷腐蚀性能比基体高3---5倍多. (2) 随着冲刷速率的提高, 4种材料的冲刷
腐蚀交互作用失重率在冲刷腐蚀总失重率中所占比例显著增大,由低速时的45%增加到高速时的80%,
从而使冲刷腐蚀交互作用失重率在冲刷腐蚀总失重率中占主导地位.(3) 在纯腐蚀中, Ni60JH涂层和1Cr18Ni9Ti不锈钢以均匀腐蚀为主要特征,
而Delelo50涂层和20钢以选择性腐蚀为主要特征.
关键词:
Ni基合金涂层
,
low carbon steel
,
erosion and corrosion
张林
,
张彩碚
,
王元明
金属学报
采用低碳钢连续冷却过程中奥氏体→
铁素体相变的元胞自动机模型, 模拟了铁素
体晶粒形核与生长的全过程, 模型中考虑了
溶质扩散在相变过程中的作用.在元胞自动机的网格
内, 晶粒的形核与生长用两个概率的变化来描述它们
之间在相变过程中的相互竞争关系, 给出了
形核与生长的元胞自动机规则.总结了元胞自动机
方法解决铁素体晶粒形核与生长问题的过程,
并在该模型的基础上分析了冷却速率等因素对于晶粒形核与生长的影响.
关键词:
相变
,
computer simulation
,
low carbon steel
HUANG Zheng Institute of Physics
,
Academia Sinica
,
Beijing
,
ChinaYAO Mei Harbin Institute of Technology
,
Harbin
,
China Institute of Physics
,
Academia Sinica
,
Beijing 100080
,
China
金属学报(英文版)
On the basis of analysis of low carbon steel fracture macro-features and micro-processes at low temperature,the definition was given of the characteristic transition temperature of brittleness,T_(pm),and its physical meaning was expounded.Discussion was carried out of phys- ical characteristic of variation at T_(pm) in respect of the fracture toughness and property of crack arrest.In addition,research was made on the application of T_(pm),which can give infor- mation about the transition of the fracture toughness,the property of crack arrest and critical crack size,to estimation the brittleness of low carbon steel at low temperatures.
关键词:
low carbon steel
,
null
,
null
,
null
,
null
LI Daoming YAO Mei Harbin Institute of Technology
,
Harbin
,
China Box 617
,
Harbin Institute of Technology
,
Harbin
,
China
金属学报(英文版)
The effect of notch depth on the cryogenic fracture behavior has been studied using a low car- bon steel.An analysis was made for the fracture features at T_c~*(cryogenic brittleness-char- acteristic temperature)at which the facture load reaehes a valley value.Furthermore,accord- ing to the experimental results and engineering design practice,a concept of critical notch (crack)'size for cryogenic brittleness,a_c,as well as its limit value a_c~*,was put forward and recommended to be a basic characteristic parameter for controlling the brittleness. Mathematical derivation was carried out to give the expression of a_c and a_c~*,the reliability of which was verified by the modeling tests under both static and cyclic loading conditions.
关键词:
low carbon steel
,
null
,
null
ZHANG Lixin Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang
,
ChinaQU Zhe LI Liguang WEI Wenduo Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
China ZHANG Lixin Associate Professor
,
Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang
,
China
金属学报(英文版)
The present work is to study the effect of phosphorus on the annealing texture of a low carbon steel at different cold rolling and annealing condition by means of pole-figure,inverse-pole figure and orientation distribution function(ODF)method.The microstructure and distribu- tion of phosphorus in steel sheet are studied by means of metallography,scanning electron mi- croscope(SEM)and electron probe microanalysis(EPMA).The results show that phos- phorus promotes the formation of the fiber texture of〈011〉parallel to the rolling direc- tion and〈111〉normal to the sheet surface.The texture was found to be affected mainly by preannealing temperatures,promoted at 390 or 590℃,and retarded at 490℃.At the preannealing temperature promoting the formation of texture,phosphorus segregation to the interior of grains was observed.It seems that the formation of the fiber texture may be associ- ated with the segregation of phosphorus.
关键词:
low carbon steel
,
null
,
null
