京九铁路孙口黄河特大桥调平钢垫片多元共渗防腐工艺研究

Study on Corrosion Protection by Multicomponent Diffusion Process for Leveling Steel Gasket for Sunkou Yellow River Super Bridge of Beijing-Kowloon Railway

为有效抑制铁路桥梁调平钢垫片在多种因素作用下的腐蚀问题,通过现场调研、分析,选择气体多元共渗工艺对调平钢垫片作用面进行改性处理,并对处理后的调平钢垫片进行电化学电试验。电化学试验结果表明,自腐蚀电位最高达-0.4845 V,自腐蚀电流密度最低为1.187×10^(-6)mA。采用炉内温度为640℃,氯化铵流量为4.4 mL/min、氨气流量为0.9 mL/min的工艺方案对调平钢垫片进行表面改性处理后,开展试服役试验。试服役试验表明,处理后的调平钢垫片接触作用面无任何锈点,渗层相对完整,显著增强调其接触面的耐腐蚀性。

In order to effectively inhibit the corrosion of leveling steel gasket on railway bridge under the action of many factors,through onsite research and analysis,the gas multicomponent diffusion technology is selected to modify the leveling steel gasket action surface,and electrochemical electric test is carried out for the treated leveling steel gaskets.The electrochemical test results showed that the selfcorrosion potential is up to-0.4845 V and the selfcorrosion current density is as low as 1.187×10^(-6)mA.Using the process program including furnace temperature of 640℃,ammonium chloride flow rate of 4.4 mL/min,ammonia flow rate of 0.9 mL/min,the leveling steel gasket surface is modificated and treated,and trial service test is carried out.Trial service test shows that after treatment of the leveling steel gasket,there is no any rust point on its contact surface,the penetration layer is relatively complete,and its contact surface corrosion resistance is significantly enhanced.