(1. 合肥工業(yè)大學 材料科學與工程學院,合肥 230009;
2. 安徽省電力科學研究院 材料所,合肥 230601)
摘 要: 在模擬大氣腐蝕環(huán)境中,采用干/濕NaHSO3+NaCl水溶液鹽霧試驗研究鋼芯鋁絞(ACSR)導線腐蝕產物的相組成及腐蝕層結構,討論其腐蝕機理。結果表明:ACSR導線中單股鋁線或鍍鋅鋼芯線的腐蝕主要表現(xiàn)為點蝕,腐蝕產物組成復雜,主要為鋅和鋁的氫氧化物、硫酸鹽與氯化物的復式鹽;在腐蝕初期,內外層鋁股線及鋼芯線表面鍍鋅層開始形成點蝕坑,逐步形成連續(xù)的腐蝕層;由于鍍鋅層和內層鋁股線之間構成原電池,因為犧牲陽極效應,鍍鋅層腐蝕速率最大;而內層鋁股線受到保護,腐蝕速率最小,外層鋁股線腐蝕速率居中。
關鍵字: 鋼芯鋁絞導線;大氣腐蝕;顯微結構;腐蝕機理
atmospheric corrosion and corrosion mechanism
(1. School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China;
2. Materials Department, Anhui Institute of Electric Power Science, Hefei 230601, China)
Abstract:The dry/wet NaCl+NaHSO3 atmosphere-salt spraying experiment of the aluminum conductor steel reinforced (ACSR) conductor was carried out to study the phases and microstructures of corrosion products and the corrosion mechanism in simulated air corrosion condition. The results show that the ACSR conductor is mainly corroded by pitting corrosion. The corrosion layer mainly consists of hydroxides, sulfates and sulfate-chloride double salts and their hydrates of Zn and Al. At the initial corroding stage, the corrosion pits form on the Al strands and the galvanizing Zn layer, which are gradually replaced by the continuous corrosion layers as prolonging the spraying time. In the ACSR conductor, a primary cell is generated between the galvanizing Zn layer and the internal Al layer in the electrolyte. In the cell, as an anode, the galvanizing Zn layer is violently etched, contrarily, as a cathode, the internal Al layer is protected. In the ACSR conductor, the sequence of the corrosion rate from high to low is the galvanizing Zn layer, the external Al layer and the internal Al layer.
Key words: ACSR conductor; atmospheric corrosion; microstructure; corrosion mechanism


