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将稀土氮碳硼共渗技术应有和于45钢制CYB-57TH-7.3-1.2型整体抽油噘筒的表面处理,可使内径57mm、长度7300mm的整体泵筒在直线度基本不变、径向总变形量小于0.050mm的前提下,获得层深达0.4mm,表面最高硬度940~1050HV的稀土氮碳硼渗层,其性能指标达到或超过了美国API标准。油田实验结果表明,在含砂量高、腐蚀严重的稠油井中,其泵效和使用寿命明显高于镀铬和引进美国技术的 相似文献
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针对不同稀土Ce含量的低镍铬锰氮奥氏体不锈钢,采用电化学动电位再活化法和Cu-CuSO4-16%H2SO4热酸浸泡法研究了两种热处理状态下不同铈含量试样的晶间腐蚀程度。研究结果表明:两种热处理状态下,未添加稀土试样腐蚀最严重。不同稀土含量的试样750℃敏化处理2 h比650℃敏化处理2 h腐蚀程度略重。从两组试验的金相显微组织照片和EPR活化率数据来看,两种热处理状态稀土Ce含量为0.053%时奥氏体不锈钢抗晶间腐蚀能力最强,但当铈含量增加到0.067%时,试样腐蚀又开始恶化。 相似文献
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用电化学测量和表面分析方法研究了钇离子注入对304L奥氏体不锈钢耐水溶液腐蚀改性作用。结果表明,在适当的注入剂量下,注入试样在0.5mol/LH2SO4、0.6mol/LNaCl水溶液中的自腐蚀电位正移,自腐蚀电流密度下降至原来的1/4~1/6,击穿电位上升30~50mV。通过离于注入方式添加的钇以过饱和固溶形式均匀分布在不锈钢表面。试样表面层内Cr/Fe比值增加,含氧层厚度也增加。钇对不锈钢耐水溶液腐蚀改性主要是通过表面合金化和改变不锈钢表面层成分实现的。研究表明,注入剂量的变化对材料的改性效果具有一定的影响。 相似文献
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采用包内孕育法研究了稀土和氮对高碳当量灰铸铁耐腐蚀性和抗氧化性的影响。灰铸铁采用中频感应电炉熔炼,化学成分为C34%~35%,Si23%~24%,Mn070%~075%。稀土和氮采用稀土硅铁合金和锰氮铁合金以孕育剂形式加入。研究结果表明,... 相似文献
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农用混合稀土对小鼠某些免疫功能的影响 总被引:7,自引:2,他引:7
报道了农用混合稀土对LACA小鼠某些免疫功能的影响,用液相单层溶血空斑法来测定腹腔一次染毒混合稀土第5天,小鼠脾脏抗体生成细胞(PFC)的变化,发现在0.1mg/10g体重剂量组,混合稀土对1gMPFC的产生有明显的刺激作用(P<0.001);0.5mg/10g体重剂量还引起了脾脏和胸腺重量的下降,为MTT颜色显示法观察了腹腔染毒10天T淋巴细胞增殖能力的变化。发现在0.1、0.5和1.0mg/1 相似文献
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用双(2,4,4-三甲基戊基)膦酸-Span80-甲苯乳状液膜研究了稀土离子的迁移行为。当膜相含10x10 ̄(-3)~3.0x10 ̄(-3)mol/L双(2,4,4-三甲基戊基)膦酸和2%~4%(W/V)Span80,内相含0.50~2.0mol/LHCl,外相的pH为3.5~50时,所有稀土离子都能快速并完全迁移。根据各稀土离子在此乳状液膜体系中迁移性质的差别,控制外相酸度,试验了稀土离子相互之间的分离情况。试验表明,用此乳状液膜体系分离稀土离子有良好的应用前景. 相似文献
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合金元素及模拟热处理对2205双相不锈钢之孔蚀性质影响 总被引:3,自引:0,他引:3
本文研究了Ni元素及不同模拟焊后热影响区(HAZ)组织对2205双相不锈钢孔蚀性质之影响。结果发现:在研究成分范围内,不同Ni含量对于底材电化学极化曲线之影响不大,其Enp和Enp均在1100 ̄1200mV之间。 相似文献
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Corrosion and tribocorrosion behaviour of super‐thick diamond‐like carbon films deposited on stainless steel in NaCl solution 下载免费PDF全文
Jibin Pu Junjun Wang Dongqing He Shanhong Wan 《Surface and interface analysis : SIA》2016,48(6):360-367
Super‐thick diamond‐like carbon (DLC) film is a potential protective coating in corrosive environments. In the present work, three kinds of DLC films whose thickness and modulation periods are 4 µm and 3, 21 µm and 17 and 21 µm and 7, respectively, were fabricated on stainless steel. The effect of different thickness and modulation periods on corrosion and tribocorrosion behaviour of the DLC‐coating stainless steel was investigated in 3.5 wt% NaCl aqueous solution by a ball‐on‐flat tribometer equipped with a three‐electrode electrochemical cell. The DLC‐coating stainless steel served as a working electrode, and its OCP and potentiodynamic polarization were monitored before and during rubbing. The wear–corrosion mechanism of the DLC films was investigated by SEM. The results showed that the increasing thickness can prolong significantly lifetime of DLC films in NaCl aqueous solution. In particular, the modulation period has a significant impact on the tribocorrosion resistance of the DLC super‐thick films. The study suggested that the increasing thickness of compressive stress layer could suppress film damage by reducing crack propagation rate. Thus, the super‐thick DLC film with thickness of 21 µm and 7 periods presented the best tribocorrosion resistance among all studied films. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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U. León-Silva M. E. Nicho J. G. González-Rodríguez J. G. Chacón-Nava V. M. Salinas-Bravo 《Journal of Solid State Electrochemistry》2010,14(6):1089-1100
The effect of thermal annealing of poly(3-octylthiophene) (P3OT) coatings on the corrosion inhibition of stainless steel in
an NaCl solution was investigated. P3OT was synthesized by direct oxidation of the 3-octylthiophene monomer with ferric chloride
(FeCl3) as oxidant. P3OT films were deposited by drop-casting technique onto 304 stainless steel electrode (304SS). 304SS coated
with P3OT films were thermally annealed during 30 h at different temperatures (55°C, 80°C, and 100°C). The corrosion resistance
of stainless steel coated with P3OT in 0.5 M NaCl aqueous solution at room temperature was investigated by using potentiodynamic
polarization curves, linear polarization resistance, and electrochemical impedance spectroscopy. The results indicated that
the thermal treatment at 80°C and 100°C of P3OT films improved the corrosion resistance of the stainless steel in NaCl solution;
the speed of corrosion diminished in an order of magnitude with regard to the 304SS. In order to study the temperature effect
in the morphology of the coatings before and after the corrosive environment and correlate it with corrosion protection, atomic
force microscopy and scanning electron microscopy were used. Morphological study showed that when the films are heated, the
grain size increased and a denser surface was obtained, which benefited the barrier properties of the film. 相似文献
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建立了一种在氮气和氢气的还原性混合气氛和1100 ℃条件下加热商业不锈钢箔(304)制备MnCr2O4尖晶石纳米线的简单方法, 并研究了不同气氛对纳米线生长的影响. 研究发现, 混合气体中氢气含量的变化会影响纳米线的形貌和产率; 而氧化性气氛(如空气)下则得不到纳米线. 在还原性气氛下, Mn和Cr原子可以和反应室内残留的痕量氧反应生成MnCr2O4尖晶石, 而Fe和Ni原子不能被氧化, 但是Fe和Ni可以起到催化纳米线生长的作用, 纳米线的生长机理属于自催化性的气-液-固(VLS)机制. 相似文献
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稀土对9Cr2Mo钢抗热冲击性能的影响 总被引:5,自引:5,他引:0
利用X射线衍射仪和金相方法研究了稀土元素对9Cr2Mo冷轧辊钢抗热冲击性能的影响,试验结果表明,稀土元素抑制了热影响区回火时碳化物的析出,从而提高了9Cr-2Mo钢热冲击性能。 相似文献