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991.
C.S. Abima S.A. Akinlabi S. Hassan O.S. Fatoba E.T. Akinlabi 《Materialwissenschaft und Werkstofftechnik》2020,51(6):817-822
This paper reports on the corrosion behavior of aluminum metal inert gas (MIG) welds reinforced with copper powder particles. Pure aluminum, AA1100 sheets, machined to a 45° v-grooved were used for this experiment. Copper powder particle reinforced samples and unreinforced samples were investigated. The corrosion behavior of the samples were investigated in 3.5 % sodium chloride (NaCl) solution, using the potentiodynamic polarization technique. The results revealed that the corrosion resistance for reinforced samples were higher than those for unreinforced samples. Hence the corrosion resistance of aluminum AA1100 welds can be improved by the addition of copper powder particle in the weld seam, and it is therefore recommended for typical industrial applications. 相似文献
992.
Fang Guan Jizhou Duan Xiaofan Zhai Nan Wang Jie Zhang Dongzhu Lu Baorong Hou 《材料科学技术学报》2020,(1):55-64
Microbiologically influenced corrosion caused by sulfate-reducing bacteria(SRB) poses a serious threat to marine engineering facilities.This study focused on the interaction between the corrosion behavior of two aluminum alloys and SRB metabolic activity.SRB growth curve and sulfate variation with and with aluminum were performed to find the effect of two aluminum alloys on SRB metabolic activity.Corrosion of 5052 aluminum alloy and Al-Zn-In-Cd aluminum alloy with and without SRB were performed.The results showed that both the presence of 5052 and Al-Zn-In-Cd aluminum alloy promoted SRB metabolic activity,with the Al-Zn-In-Cd aluminum alloy having a smaller promotion effect compared with 5052 aluminum alloy.The electrochemical results suggested that the corrosion of the Al-Zn-In-Cd aluminum alloy was accelerated substantially by SRB.Moreover,SRB led to the transformation of Al-Zn-In-Cd aluminum alloy corrosion product from Al(OH)3 to Al2 S3 and NaAlO2. 相似文献
993.
交流阻抗法研究 PVD 镀层腐蚀 总被引:1,自引:0,他引:1
应用交流阻抗法评定PVD(物理气相沉积)镀层在KClO4溶液中的腐蚀,并研究了镀层孔隙与腐蚀速率之间的关系 相似文献
994.
针对穿线多管现行涂锌工艺存在的问题和管内防腐层喷涂工艺及PLC控制自动喷涂机进行分析和研究,提出用高能浸涂,工艺取代镀锌工艺和管内喷涂工艺的设想。 相似文献
995.
热管式预腐蚀器的设计与应用 总被引:1,自引:0,他引:1
开发设计的热管式预腐蚀器,用于替代小氮肥厂原用的普通列管式预腐蚀器。阐述了热管式预腐蚀器工艺设计计算、结构设计及工业应用效果。 相似文献
996.
The inhibition effect of Carboxymethylchitosan (CMCT), Cu2+, and CMCT + Cu2+ mixture on the corrosion of mild steel in 1 M HCl has been investigated using gravimetric and electrochemical techniques. CMCT + Cu2+ mixture acts much more effectively than the inhibiting action of each additive separately. In addition, higher efficiency is achieved for the mixture of 20 mg L−1 CMCT + 10−4 M Cu2+. The efficiency of the optimal mixture increases with the temperature in the range 298-353 K. Activation energy of corrosion reaction in the presence of the optimal mixture of the inhibitors is much lower than that exhibited in 1 M HCl solution. The inhibition mechanism proposed in this paper is based on the results of conductometric investigations. 相似文献
997.
采用天然大分子壳寡糖、缩水甘油三甲基氯化铵、苯甲醛为原料,合成了绿色壳寡糖衍生物缓蚀剂(BHC)。通过红外光谱、核磁共振氢谱对缓蚀剂BHC结构进行了表征。采用失重法、电化学法、扫描电镜、原子力显微镜、接触角等对缓蚀剂BHC进行缓蚀性能评价和机理分析。得到的优化缓蚀剂BHC合成条件为m(HTCOS)∶m(苯甲醛)=1.0∶2.4,反应温度80℃,反应时间24 h。在总压为15 MPa(H2S、CO2、N2分压分别为1、5和9 MPa)条件下,缓蚀剂BHC质量浓度为100 mg/L时,P110钢片在140℃、含H2S/CO2腐蚀介质中的缓蚀率为85.62%,与市售缓蚀剂相比,BHC缓蚀率提高16.90%,可有效减缓高温高含H2S/CO2腐蚀环境下钢材的腐蚀速率。缓蚀剂BHC是一种偏阴极保护的混合型缓蚀剂,在金属表面的吸附行为符合Langmuir吸附等温式,与钢表面形成稳定共价键,能很好保护钢管。 相似文献
998.
The objective of this research work is to clarify essential factors related to degradation of PEFC electrodes. The degradation of Pt catalysts and the carbon support after a daily start and stop (DSS) operation was evaluated separately by measuring the electrochemical active area (SPt) and the double layer charging current (IDL) with cyclic voltammetry without and with CO adsorption on Pt catalyst surfaces, respectively. Corrosion of the carbon support was accelerated mainly by raising the operating potential to 0.90 V, which was observed by increase in IDL. The high-temperature operation at 90 °C or high-potential operation at 0.90 V resulted in a dramatic decrease in SPt. In contrast, it was found that the apparent cell performance was not so degraded probably because the decrease in SPt was cancelled by an increase in the proton conductance in the swollen ionomer. The agglomeration of Pt catalyst particles and their migration in the electrolyte membrane were also analyzed by TEM observation after the DSS operations. 相似文献
999.
1000.
分析了焦油车间蒸馏塔腐蚀的情况,腐蚀的主要原因是固定铵盐、Cl^-、游离碳及过量的水分。采取了在焦油加工前加入Na2CO3溶液等多种防腐措施后,取得了良好的效果。 相似文献