不锈钢、镀锌钢接地材料在土壤中的腐蚀规律研究

Research of Corrosion Rule on Grounding Materials of Stainless Steel and Galvanized Steel in Soil

研究了304不锈钢和镀锌钢在变电站原土中的自然腐蚀、不同类型土壤中的电解腐蚀,以及交流直流泄流下的腐蚀。结果表明:镀锌钢在土壤中的自然腐蚀严重,304不锈钢基本不腐蚀;比较镀锌钢、不锈钢母材及不锈钢焊缝3种材料在4个地区的腐蚀失重,腐蚀率由大到小的顺序为:卤阳湖>户县>榆林>安徽;土壤中Cl-极大促进了接地网的腐蚀;交直流泄流电解腐蚀中,304不锈钢以点蚀为主,镀锌钢腐蚀严重,趋于均匀腐蚀;接地网交流电解腐蚀明显轻于直流电解腐蚀。

Natural corrosion performance in original soil of substation, electrolytic corrosion in different types of soil and discharge corrosion in direct current （dC） and alternating current （AC） on 304 stainless steel and galvanized steel were investigated. It was found that the natural corrosion of galvanized steel in soil was severe, but 304 stainless steel basically did not corrode; comparing the corrosion weight loss between three materials of galvanized steel, base material and weld of 304 stainless steel in four regions, the descending order of corrosion rate was Luyang Lake〉Huxian〉Yulin〉Anhui; C1 of the soil greatly contributed to the corrosion of grounding grid; in AC-DC discharging electrolytic corrosion, 304 stainless steel was given priority to pitting, and galvanized steel caused severe cor- rosion, tending to uniform corrosion; the corrosion degree of the grounding materials in AC electrolysis was obviously less than that in DC electrolysis.