Research On Corrosion Electrochemical Detecting Of Brass Tubes In Service And Seawater Metal Samples

The corrosion electrochemistry detecting system is mad for seawater metal samples in this paper. It is used in Zhoushan seawater corrosion station to detect the corrosion of four mild steel samples.A electrode system for detecting the corrosion of brass tubes in service is made. Brass tubes in simulated circle cooling system are studied with the electrode system.The main conclusions are as follows: Simulating tests are carry out with the electrode system for seaweter samples.The results indicate that the system is feasible to detect the corrosion of the samples. Testing on mild steel and Aluminium samples last about five months in the Jingye lake of Tianjin University. The result shows that the system can be used to detect the corrosion of the samples in field for a long time.the system is used in Zhoushan seawater corrosion station to detect the corrosion of four mild steel samples.The results show the early change of corrosion behavior of the samples.This make it possible to study the corrosion rules of metal materials in seaweter. The electrochemical impedance spectrum can be used to detect the information of corrosion on the samples. A electrode system for detecting the corrosion of brass tubes in service is made.The system has special configuration so it can be put into long tube without disturbing flow of the liquid. It is no effect to the valid testing area when the position of the electrode system change. It can detect the different corrosion state of same material and local corrosion charater at some degree. The electrode system can be used in simulated circle cooling system to detect the corrosion of brass tubes in service. The result of polarization resistance of square wave, galvanic step and potential scan are according to the result of the electrochemical impedance spectrum.The electrochemical noise technique is good for detecting the change susceptivity of local corrosion in simulated circle cooling system. The corrosion character of brass is studied in neutral sodium chloride solution.The Cl-ion hastens the anode process of brass corrosion. The cyclic voltammetric behaviour shows that the reaction of brass is quasi-reversible in neutral sodium chloride solution Electrochemical noise study shows that the current PSD plot of corroded electrode with pinhole is different from that without pore or not corroded. The current PSD plot slope of the electrode without pore is smaller than that not corroded .The slope of the potential PSD plot gets small with the degree of corrosion increasing.