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961.
在高温高压高CO2和Cl^-环境中,用静态高温高压模拟试验方法对不同浓度的TGS00新型咪唑啉季铵盐缓蚀剂进行了缓蚀效率测试.结果表明,TGS00缓蚀效率随加入量增加而增加,浓度增加到0.3g/L后,缓蚀速率提高不明显.同时研究N80套管钢表面的腐蚀产物,缓蚀剂浓度较低时,以均匀腐蚀为主,加入量提高到0.3g/L时,除局部少量点蚀外,无其它明显腐蚀特征. 相似文献
962.
963.
对仪征化纤化工厂PTA装置中反应器第一冷凝器E-112 壳体腐蚀状况进行了分析.结果表明,高温高压冷凝液的冲刷是造成E-112壳体腐蚀穿孔的 主要原因,并提出相应防护对策. 相似文献
964.
CAO Mingzhou HAN Dong ZHANG Tao LI Dong Institute of Metal Research Academia Sinica Shenyang China Associate Professor Institute of Metal Research Academia Sinica Shenyang China 《金属学报(英文版)》1993,6(2):117-120
The rapidly solidified powder of Ti-34Al-2Mn alloy was obtained by means of ultrasonicgas atomisation (USGA) technique.The tupical size of the powder is 27 μm.X-ray diffractionresults show that the powder consists of major α_2-phase and minor γ-phase.Under opticalmicroscope both equiaxed and dendritical microstructure features were observed on RS pow-der sections.After annealing at 900 ℃/for 2 h in vacuum,most of α_2-phase transforms intoγ-phase,resulting in refinement of structure. 相似文献
965.
YIN Hong TAO Kun PAN Jinsheng LI Hengde Tsinghua University Beijing China professor.Department of Materials Science Engineering Tsinghua University Beijing China 《金属学报(英文版)》1993,6(3):145-152
The critical _d vahues ( _ ) of the γ/(γ+σ).γ/(γ+μ) and γ/(γ+γ') phase boundaries insome ternar alloy phase diagrams at various temperatures are calculated by averaging the _d values of sererai selected characteristic points at the phase boundaries.Approxmateequations for the temperature dependence of the critical _d of γ/(γ+σ).γ/(γ+μ) andγ/(γ+γ') phase boundaries are established.The accuracy of the analysis is discussed in detail.It is found for the first time that the average value of the bondorder _ at the phase boundaries ts also approximatelr a constant and therefore a criticalaverage bond order _ like - can be introduced for the analysts of phase stability 相似文献
966.
LI Ximing CHEN Jiayong Institute of Chemical Metallurgy Academia Sinica Beijing ChinaR.KAMMEL Institut Für Metallurgie Technische Universitt Berlin Germany Research Assistant Institute of Chemical Metallurgy Academia Sinica Beijing China 《金属学报(英文版)》1992,5(9):153-157
The influence of mechanical activation on the leaching behaviour of scheelite was studied bymeans of fine grinding in an attritor and subsequently HCl leaching in presence of PO_4~(3-).Results showed that after fine grinding in the attritor,the reaction rate of scheelitewith HCl-Na_3PO_4 solution was remarkably increased,the extraction of W increased fromabout 8 to 99%.The IR spectra and X-ray diffraction analysis indicated that in addition toan enlargement of surface area the fine grinding action had made also changes of fine struc-ture and reactivity of solid surface,hence the leaching process of scheelite can be carried outunder mild leaching conditions. 相似文献
967.
LI Yinfeng GUO Huiqun XU Rufeng SHEN Baogen Laboratory of Magnetics Institute of Physics Academia Sinica Beijing China 《金属学报(英文版)》1992,5(11):340-345
The disaccommodation(DA)measurements of initial susceptibility were performed inamorphous Fe_(90-x)Ni_xZr_(10)(x=10,20,30)alloys.The DA was measured for two differentamorphous states:as-quenched and pretreated at 537 K for 45 min.For all the as-quenched samples,in the isochronal spectra of DA a well defined relaxation peak around350 K is accompanied by a samll but distinct peak near the Curie temperature ofFe_(90)Zr_(10) phase(T_c=230 K).The reversibility and annealing effect on DA are analyzedwithin the framework of two-level model.The fits of the theory to the experimentaldata of reversible relaxation processes gave a spectrum,of activation energies and pre-exponential factor. 相似文献
968.
双滑移取向Cu单晶的循环形变行为──Ⅱ.滑移带和形变带SCIEI 总被引:2,自引:0,他引:2
用光学显微镜和扫描电镜研究了双滑移取向([034],[117])Cu单晶循环饱和后的表面形貌,塑性分切应变幅(γpl)低于10^(-3)时,[034]晶体表面上要为主滑移系的驻留滑移带(PSBs)占据,次滑移只在边缘区域启动,其PSBs细窄(<1μm),体积百分数在1%以下.γpl>10^(-3)时,次滑移开始在试样的中部启动,同时,表面出现二种贯穿晶体的宏观形变带(DBI,DBII),滑移带在形变带内集中.[117]晶体在γpl=4.4×10^(-4)时,双滑移现象已十分明显.γpl>10^(-3)时,表面也形成与前者相似的形变带.DBI的惯习面与主滑移面平行([034]晶体)或接近([117]晶体),DBII的惯习面则与前者垂直,文章讨论了形变带形成的可能原因. 相似文献
969.
970.
LI Yundong ZHANG Tianxiang ZHENG Zhi ZHU Yaoxiao Institute of Metal Research Academia Sinica Shenyang China Professor Institute of Metal Research Academia Sinica Shenyang China 《金属学报(英文版)》1990,3(6):393-397
The solid solubilities of 15 common alloying elements added to the Ll_2-type intermetalliccompound Ni_3Si at 900°C have been estimated,and their substitution modes have been de-duced from the direction of solubility lobe of the compound.It is shown that the alloyingbehaviours in Ni_3Si are determined by both size and electronic factors,i.e.,the substitutionmode is governed by electronic configuration and solubility by the both.An interactionparameter is presented to describe quantitatively the influence of electronic configuration onsubstitution mode and the solubility limit can be successfully explained together with atom radius. 相似文献