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采用微生物分析、失重法、自腐蚀电位、EIS、动电位极化曲线和SEM等手段对比研究了45钢在无菌海水、无菌培养基、假单胞菌海水和假单胞菌培养基4种不同环境下的腐蚀行为。结果表明:腐蚀初期假单胞菌及培养基均对45钢有缓蚀作用。但随着时间的推移,假单胞菌新陈代谢作用引起了氧浓差腐蚀,且其代谢产物中的碱及铁载体的局部堆积加速了45钢的腐蚀。培养基环境对微生物腐蚀有促进作用。 相似文献
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用电化学方法和浸泡试验研究了SiC颗粒粒度和体积分数对SiCp/ 2 0 2 4Al铝基复合材料在 3.5 %NaCl水溶液中耐蚀性的影响 ,作为比较对 2 0 2 4Al的耐蚀性也进行了研究。结果表明 ,与基体相比 ,SiCp/ 2 0 2 4Al复合材料并不增加点蚀敏感性 ,其抗蚀性与SiC体积分数和粒度有关 ,SiC颗粒体积分数低或粒度高的复合材料 ,其抗蚀性往往大。 相似文献
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利用失重试验和电化学方法研究了泡沫SiC/钢双连续相复合材料在3.5%NaCl水溶液中的腐蚀行为.结果表明:多孔SiC增强体的存在对泡沫SiC/钢双连续相复合材料的腐蚀性能有一定程度的影响,其腐蚀敏感性比基体20钢稍大,这是由于基体与SiC之间的大量界面导致复合材料耐蚀性的降低,但界面处形成的金属间化合物提高了复合材料的耐蚀性.泡沫SiC增强体筋结构对其腐蚀行为有较大影响.选用致密骨架制备的复合材料的耐蚀性明显不如纯基体(45钢),主要原因是Fe与致密SiC骨架间存在电偶腐蚀倾向. 相似文献
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Bin Zhou Chi Zhang Li Yang Di Bai Emmanuel Oluwatobi Olugbade Gen-zhe Huang 《工业材料与腐蚀》2020,71(3):392-400
The corrosion behaviour of 6082 aluminium alloy was studied by measuring the electrochemical impedance spectra and electrode polarization curves. After the electrochemical tests, a microstructural analysis of the samples was conducted by using optical microscopy and electron scanning microscopy techniques to determine the corrosion mechanism. The results show that the Nyquist plot of the electrochemical impedance data in the NaCl solution consists of high- and low-frequency capacitive impedance loops. When ions are added to the NaCl etchant, the Nyquist plots of the electrochemical impedance data are composed of two different curves: a high-frequency capacitive impedance loop and a low-frequency inductive impedance loop. The corrosion current density increases with increasing concentration, and as a result, the corrosion resistance of the aluminium alloy decreases. The microstructures of 6082 aluminium alloy consist of Mg2Si secondary particles in a large α-Al matrix. Pitting corrosion initially occurs at the boundary between the matrix and secondary particles because the electrode potentials of the matrix and secondary particles are different. Then, corrosion paths develop along the network-like grain boundaries, and finally, massive network-like corrosion occurs throughout the entire alloy. 相似文献
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为了了解不同材料在微细电火花线切割(MWEDM)加工下的表面耐蚀性,分别对W18Cr4V,60Si2Mn和M42三种材料进行加工,借助微电解池装置和电化学工作站对各试件做表面耐蚀性试验,进行电化学阻抗谱和动电位极化曲线测量分析,采用倒置金相显微镜对腐蚀后的表面进行拍照观察并与平磨加工表面进行对比.结果表明,微细电火花线切割加工表面耐蚀性整体优于平磨加工表面;对于不同材料,MWEDM表面耐蚀性存在显著差异;对于同种材料,选取适当的加工参数能够得到耐蚀性较好的表面. 相似文献
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A comparative study has been undertaken on the behaviour of AISI 304 steel in Postgate medium with and without the presence of Desulfovibrio desulfuricans subspecies desulfuricans bacteria (strain DSM 642). Electrochemical studies were carried out with open circuit potential measurements, linear polarization, electrochemical impedance spectroscopy (EIS) and scanning electronic microscopy (SEM). In Postgate medium without bacteria, and as expected in stainless steels, the formation is observed of a protective surface passive film on the AISI 304 steel. On measuring the corrosion potentials (Ecorr), it is noted that the potential tends to rise with the immersion time, and in the impedance graphs an increase is observed in the charge transfer resistance and a higher phase angle with respect to the other systems tested. However, in Postgate medium with Desulfovibrio desulfuricans (strain DSM 642), the tendency of the corrosion potentials (Ecorr) is not uniform, though the recorded values are less noble than those for the medium without bacteria. A variation is observed in the properties of the layer of corrosion products in the presence of bacteria as the immersion time advances (due to the effects caused by the formation of corrosion products which gives rise to changes in the corrosion speed). 相似文献
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采用油相分离的方法对水溶性亚硝酸钠进行微胶囊化,然后利用锐孔—凝固浴的方法以海藻酸钙作为囊壁进行再包封制备亚硝酸钠微胶囊.测试了亚硝酸钠微胶囊的缓释性能,并使用极化曲线和电化学阻抗法对亚硝酸钠微胶囊缓蚀剂性能进行了评价. 相似文献
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Three types of methylcyclohexane (MCH) coating were deposited as interlayer dielectrics on copper using plasma-enhanced chemical vapor deposition (PECVD) at three different RF plasma power levels. The coating performance was then evaluated by an electrochemical im pedance spectroscopy (EIS) and a potentiodynamic polarization test in 3.5 wt.% NaCl solution. An atomic force microscopy (AFM) and Fourier transform infrared reflection (FT-IR) spectroscopy were also conducted to analyze the coatings. The MCH coatings showed a lower corrosion rate than the copper substrate in the potentiodynamic tests. The EIS results showed that the corrosion resistance of the coatings increased with an increasing plasma power. Thus, the MCH films with an increasing plasma power improved the corrosion resistance due to the formation of a low-porosity coating, the enhanced formation of C−H, C−C, and C≡C stretching configurations, and the improved smooth surfaces. 相似文献
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前处理对化学转化处理铝锂合金耐蚀性的影响 总被引:1,自引:1,他引:0
采用手工脱氧、打磨脱氧、浸渍脱氧三种不同的前处理工艺对新型2198铝锂合金进行前处理,之后手工刷涂Alodine1200s化学处理液进行化学转化处理。通过极化曲线和交流阻抗谱,研究了所得试样在3.5%NaCl溶液中的腐蚀行为,并结合微观形貌分析,研究了前处理方式对试样耐蚀性的影响。结果表明:打磨脱氧前处理的试样击穿电位最正,自腐蚀电流密度最低,容抗弧半径最大,阻抗模值最大,低频段阻抗相位角最接近于-90°,耐蚀性最好。 相似文献
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Seung Eon Kim Jung Hyun Son Yong Taek Hyun Hi Won Jeong Yong Tai Lee Jae Sung Song Jun Hee Lee 《Metals and Materials International》2007,13(2):151-154
Electrochemical corrosion behaviors of novel beta titanium alloys, Ti−30Ta−10Nb−10Zr, Ti−40Ta−10Nb−10Zr and Ti−40Ta−10Nb−4Sn
were characterized in naturally aerated Hank's solution at 37°C compared with currently used biomedical titanium alloys. Ti−30Ta−10Nb−10Zr
and Ti−40Ta−10Nb−10Zr exhibited comparable corrosion resistance to CP Ti or Ti−6Al−4V, while the corrosion resistance of Ti−40Ta−10Nb−4Sn
was greatly inferior to the other alloys. An EIS data analysis confirmed that the resistance of passive film for Ti−30Ta−10Nb−10Zr
and Ti−40Ta−10Nb−10Zr was comparable to CP Ti or Ti−6Al−4V. Ti−30Ta−10Nb−10Zr and Ti−40Ta−10Nb−10Zr alloys are promising metallic
biomaterials for the future, owing to their very low elastic modulus and good corrosion resistance capabilities. 相似文献
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用电化学方法和腐蚀失重法研究了 2024Al和SiCp/2024Al复合材料在 3.5%NaCl水溶液中的耐蚀性,用电化学阻 抗技术对它们的硫酸阳极氧化膜保护性进行了跟踪评价.结果表明SiCp/2024Al在 3.5%NaCl水溶液中比 2024Al有较大的 腐蚀敏感性.2024Al表面的阳极氧化膜,经热水封闭后,可提供相当好的保护作用.热水封闭的Sip/2024Al阳极氧化膜, 具有良好的耐 NaCl溶液腐蚀能力,由于氧化膜中SiC颗粒的存在破坏了氧化膜的完整性和均匀性,故其耐蚀性不如 2024 Al 合金的阳极氧化膜. 相似文献
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黄铜管腐蚀监测传感器的研制 总被引:5,自引:2,他引:3
设计制作了用于对电厂凝汽器H70/30黄铜管进行监测的传感器。采用电厂实际使用过和未经使用的黄铜管制作电解池,用制作的传感器测量了黄铜管的电化学阻抗谱和极化阻力。结果表明,该传感器可以用于对黄铜管的腐蚀进行监测。 相似文献
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Investigations concerning the electrochemical corrosion behavior of mould steels are scarce and limited. In the present study, the corrosion resistance of a precipitation hardening moulds steel submitted to aging treatments has been assessed in a 0.1 M NaCl aqueous solution by means of potentiodynamic polarization and electrochemical impedance spectroscopy measurements. The electrochemical characterization of the steel not submitted to hardening treatments was also examined and a comparative study was made between the different specimens. Scanning electron microscopy and electron probe microanalysis were used to obtain information about the morphology and chemical composition of the steels surface after the electrochemical tests. Increasing the aging temperature an increase of secondary hardness is observed, attributable to an increase of secondary phases (re‐precipitated carbides and metastable GP zones) amount, positively reflecting on the mechanical properties. However, the electrochemical results show a progressive worsening of the corrosion behavior, the as‐received steel sample exhibiting the best corrosion resistance. The observed decrease of corrosion resistance with increasing the aging temperature is ascribed to enhanced galvanic coupling phenomena between the secondary phases, acting as cathodes, and the surrounding matrix which, consequently, experiences preferential dissolution. 相似文献
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《中国有色金属学会会刊》2020,30(1):90-98
Zirconium oxide nanoparticles with 0.4 wt.% and 0.8 wt.% are incorporated into the Al—0.65Mg—0.05Ga— 0.15Sn (wt.%) alloy anode (base alloy) in order to improve the performance of the resulting anodes. Electrochemical characterization of the reinforced alloys was done by potentiodynamic polarization, electrochemical impedance spectroscopy and galvanostatic discharge and corrosion behavior was evaluated using self-corrosion rate and hydrogen evolution in 4 mol/L KOH solution. The surface morphology of the alloys was also studied using field emission scanning electron microscope (FESEM). The obtained results indicate that the base alloy shows high corrosion rate in 4 mol/L KOH solution by releasing 0.47 mL/(min·cm2) hydrogen gas, whereas the alloy containing 0.8 wt.% ZrO2 provides the lowest hydrogen evolution rate by releasing 0.32 mL/(min·cm2) hydrogen gas. Furthermore, by increasing zirconium oxide nanoparticles, the corrosion current density of the aluminum anodes is decreased and their corrosion resistance increases significantly compared to the base alloy in alkaline solution. In addition, nanometer-sized zirconium oxide incorporated anodes exhibit the improved galvanic discharge efficiencies, so that 0.8 wt.% nano-zirconium oxide incorporated base alloy displays the highest power density and anodic utilization compared with the others in 4 mol/L KOH solution. 相似文献