Comprehensive Study On Thermal Erosion Of Typical Turbine Blades

As a kind of energy conversion device,turbine is becoming more and more widely used in industry.As the turbine running the high temperature dust-laden gas will inevitably erode the surface of the turbine blades,not only destroy aerodynamic performance of it,but also may make its components and equipment failure,resulting in economic and reliability are reduced.Therefore,it is necessary to study the erosion of blade under the conditions of mufti-temperature,full-angle and variable-size of particle.The following results were obtained by comparing erosion rate change analysis of the base material of steels(1Cr12Mo、X20Cr13、2Cr12NiMo1W1V、GH738),C1 coating(sprayed on 1Cr12 Mo surface)and strengthen X20Cr13 specimen in different temperature,different angle of attack,and different particle size of quartz sand grains: The mass loss of the specimen was approximately linear with the mass of the sand eroded.And the erosion rate was the largest in the range of 10°-35°,and the erosion rate was the smallest in the range of 80°-90°,showing plastic erosion characteristics.The erosion rate of different leaf materials changes with temperature,and the erosion rate did not show the increase with temperature,or vice.Under the experimental conditions,the corrosion resistance of 1Cr12 Mo was better than that of the other three substrates at 200 ℃-300 ℃,the substrates erosion resistance of 2Cr12NiMo1W1 V and GH738 was better than the other two at 400℃,2Cr12NiMo1W1 V erosion resistance was better than that of GH738 at 500℃.Under the same experimental conditions,the erosion rate of 500-mesh sand particles was significantly less than that on the 200-mesh;Because of the process conditions,C1 coating appeared to fall off and did not show significant erosion resistance.Experiments showed that X20Cr13 material by the steel shot after surface treatment did not enhance its ability to resist erosion.Through analyzed the micro structure of the specimens by electron microscope(SEM),we found that :At low angle,the cutting marks on the surface of the specimen were mainly shovel and plow,The erosion mechanism followed the Micro-cutting Theory.At high angle,the cutting marks on the surface of the specimen are mainly extrusion lip,the erosion mechanism followed the Extrusion-flaking Theory.Erosion during the incubation period was weightless because the material by the impact of deformation strain did not meet the critical damage deformation strain,so that no surface debris.When the large particles eroded the surface of the specimen,it had large kinetic energy and the conversion of heat was also large,so that most of the material directly separated from the surface,there was no residual debris on the surface;By observing the surface morphology of the specimen,it was proved that the reason of the high erosion rate of the C1 coating was caused by the coating falling off during the erosion process.