Study On Sand Erosion Resistance Of Steel Structure Coatings Under Multi-Factor Influence

This project is aimed at the long-term erosion and aging of steel structures in Mongolia,China,and the high-low temperature environment and strong ultraviolet environment.The aging and damage of the polyurethane coating on the steel structure surface leads to the deterioration of the durability and safety performance of the steel structure.Loss,resulting in local and overall failure of the steel structure,the sand-resistant erosion performance of the steel structure polyurethane coating in the sand erosion environment,high and low temperature aging,ultraviolet radiation aging conditions.The project was subject to the National Natural Science Foundation of China,“Research on the Erosion Mechanical Behavior and Damage Evaluation of Steel Structure Coatings in Sandy Environment”(Grant No.: 11162011);Study on the Mechanism of Sand Structure Erosion Damage of Steel Structure Coatings in the Great Temperature Difference of Inner Mongolia and Inner Mongolia("Approval No.: 11862022").The sand blasting test,the high and low temperature cycle aging test and the ultraviolet aging test of the steel structure polyurethane coated test piece are carried out by using the simulated wind and sand environment erosion test system,the simulated natural environment erosion test box and the ultraviolet aging test box,and the test is performed on different aging conditions,Comparative analysis of sand erosion resistance of steel structure coatings under different degrees of aging.The following is the specific research content:1.Analyze the natural environment characteristics of China's Inner Mongolia,including the sand environment,high and low temperature environment and ultraviolet environment;design high and low temperature cycle aging test,ultraviolet aging test and sand erosion test of steel structure polyurethane coating under different working conditions.2.The sand-resistant erosion test of the steel structure polyurethane coating is carried out.The test method adopts the airflow sand blasting method,and the experimental instrument adopts the simulated sand-sand environmental erosion test system to study and analyze the sand-resistant erosion resistance of the coating and draw conclusions.: The erosion of the steel structure polyurethane coating is not divided into the low speed increasing stage and the high speed increasing stage.Under different erosion speeds,the erosion rate of the coating increases with the erosion angle.The trend of increasing first and then decreasing is shown;the test results show that the maximum erosion rate of the coating is 38°.3.The high temperature and low temperature cycle aging test was carried out on the steel structure polyurethane coating.The morphology of the coating before and after aging was observed by scanning electron microscopy(SEM).The coating showed obvious changes after aging;the X-ray energy spectrum(EDS)was used.The elements before and after aging of the coating were analyzed,and the content of the elements before and after the coating surface was found to change.X-ray diffraction(XRD)was used to analyze the phase change of the crystal before and after aging of the coating.4.The sand-blasting test of the coating after aging and high-temperature cycle is carried out to study the sand-resistant erosion resistance of the coating after aging.The effects of temperature cycle aging on the sand-resistant erosion resistance of the steel structure polyurethane coating are analyzed from various aspects.The results show that the sandblasting resistance is significantly reduced after temperature cycle aging.The surface morphology and roughness of the coating are observed by scanning electron microscopy(SEM)and laser confocal microscopy(LSCM).5.Ultraviolet aging test of steel structure polyurethane coating,scanning electron microscopy(SEM)was used to observe the morphology of the coating before and after aging,and the coating showed obvious changes after aging;the coating was analyzed by X-ray energy spectroscopy(EDS).Before and after the aging of the layer,the content of the elements before and after the surface of the coating was found to change.X-ray diffraction(XRD)was used to analyze the phase change of the crystal before and after aging of the coating.6.The sand blasting test was carried out on the UV-aged coating to study the sand-resistant erosion resistance of the aging coating.The effects of UV aging on the sand-resistant erosion resistance of the steel-structured polyurethane coating were analyzed from various aspects.The results showed that: The sand-resistant erosion resistance was significantly reduced after UV cycle aging.The surface morphology and roughness of the coating were observed by scanning electron microscopy(SEM)and laser confocal microscopy(LSCM).