Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： Corrosion failure process of Al-alloy parts of knife switches in Hainan power grid was investigated by means of metalloscope and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X- ray diffraction (XRD). The results show that the material of breaker action bar is as-extruded LY12 Al-alloy, the matrix phase of which contains precipitates of CuAl2 thereby, with a higher tendency to intergranular corrosion. Certain light grains are observed in the matrix, which may result in dramatic decrease of mechanical properties. Severe exfoliation corrosion is developed due to the synergistic of intergranular corrosion and stress, while the plated tin layer peeled off preferentially by the attack of corrosive substances containing Cl and S from the island environment and industrial pollution, thereby the substrate exposures. Meanwhile, Al and its alloys may still be protected by the oxide scale formed spontaneously on their surface. In general Al-Cu alloys cannot be applied at all, but Al-Si alloys can be used safely in Hainan island.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： Cold galvanizing coatings were prepared. The coating properties were characterized by salt spray test and electrochemical impedance spectroscopy. Among others, the coating with 95.2% (mass fraction) Zn exhibits the highest corrosion resistance to salt spray, and its corrosion product consists of ZnO and Zn(OH)2. When the Zn content is less than 75%, the impedance of coatings in the solution of 3%(mass fraction) NaCl decreases with the increasing immersion time, and thus the coatings provide inferior protectiveness; when the Zn content is greater than 75%, the impedance of the coating decreases firstly and then increases with the increasing time, which may be ascribed to that the Zn powder in the coating acts as sacrificial anode，which was preferentially corroded in the initial statge.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract： none
Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract：针对海南省内变电站接地网土壤腐蚀问题，对海南境内17个地区，共计33所变电站（11座35kV变电站，17座110kV变电站和5座220kV变电站）进行调研，对变电站接地网实际腐蚀程度进行了分类。同时对海南省各变电站接地网所处土壤环境的腐蚀等级进行评价，结果显示，33所变电站内土壤腐蚀等级为C2~C5级，其中处于C2级的仅8个，占24.2%，属轻度腐蚀；处于C3级的15个，占全部的45.5%，属中等腐蚀；处于C4、C5级的10个，占全部的30.3%，为严重腐蚀、重度腐蚀；对海南省各变电站内直流杂散电流强弱程度进行测量，均处于中、高级。分析了接地网土壤腐蚀的原因。
Hits
Hits
Downloads
Comment