Sealing Reprocessing Of Iron-based Amorphous Coating And Its Environmental Adaptability Evaluation

Iron-based amorphous coatings are widely used in equipment in extreme marine environments due to their ultra-high strength,hardness,and good corrosion resistance.However,due to the limitations of the current process and other factors,the spraying preparation process causes different types of pore defects after the coating is prepared,which greatly reduces its service life and leads to huge losses in engineering.In view of the pore defects inherent in the iron-based amorphous coatings used in the marine atmospheric environment,this subject research has obtained a plugging reprocessing technology,which aims to effectively seal the coating pores without changing the surface state,thereby improve its corrosion resistance.On the basis of studying the sealing inhibitor,this subject studied the corrosion behavior of the coating before and after sealing treatment and the mechanism of sealing effect.Finally,four artificial accelerated corrosion tests actually verified the resistance before and after sealing treatment Corrosion performance difference,and evaluate its environmental adaptability.The following results were obtained through the above three parts of research:The research shows that the corrosion inhibitor for iron-based amorphous coating substrate L921A steel has an anode action coefficient of 0.1 1,a cathode action coefficient of 0.13,and a negative and anode action coefficient ratio of 0.85,indicating that the corrosion inhibitor belongs to the anode type corrosion inhibitor;And its corrosion inhibition rate can reach more than 96%;in the environment of 25?,increase the corrosion inhibitor concentration by 4 times,and add 20%ethanol to statically immerse the coating for 6h,then dry naturally to achieve effective coating pore After plugging,the polarization resistance of the coating after sealing can be increased by 4.7 times.The sealing inhibitor for iron-based amorphous coatings can also effectively inhibit the anode corrosion process of the coating.Research on the corrosion behavior of the coating before and after sealing treatment found that the corrosion reaction mainly originates from the substrate.Sealing and reprocessing can effectively reduce the corrosion weight loss of the coating system and macroscopically improve the corrosion resistance of the coating system;through EDS and FTIR found that the sealing agent can penetrate into the coating and form a dense film.SEM can see the effective physical plugging of pores by sealing reprocessing;XRT found that the number of pores inside the coating and the equivalent pore size after sealing were reduced to a certain extent,and the average porosity decreased from 2.19%to 1.39%.The study of electrochemical characteristics shows that the pore sealing agent also has a certain corrosion inhibition effect,and the location of the pore distribution in the coating can be explored by SVET technology to predict the corrosion occurrence area.The final salt spray test,damp heat test,and accelerated test of marine atmospheric environment show that the corrosion resistance of the coating is steadily enhanced after sealing and reprocessing,and the environmental adaptability is significantly improved;the supersonic flame erosion test shows that the sealing and reprocessing will not apply The mechanical properties of the layer have an impact.