Investigation on the erosion characteristics of martensitic blade steel material 1Cr12W1MoV by micro-particle swarm with high velocity

Abstract Based on the microscopic morphology and size distribution of the iron oxide scales measured in our erosion tests, 109 micro flaky particles were elaborately generated by MATLAB codes to ensure that the morphology and size distribution were basically consistent with the observations under the microscope. Furthermore, based on the nonlinear explicit dynamics software ABAQUS/explicit, the numerical simulations of the erosion mechanism of multi-particles on the blade substrate 1Cr12W1MoV in a high-parameter turbine were performed. Compared with the experimental data, the influence of the particle shape, particle size, impact velocity and particle roundness on the erosion rate was studied in detail. The results show that the shape of the particles has a great effect on the erosion rate. The impact angle corresponding to maximum erosion rate of the flaky particles is around 24°–30°. While the equivalent maximum impact angle is around 45°–60° for spherical particles. The effect of micro-cutting on erosion is greater than that of extrusion-forging for flaky particles. While the influence of micro-extrusion and forging on erosion is huger than that of micro-ploughing for spherical particles according to the morphologies results. In addition, the higher the roundness of the flaky particles, the lower the erosion rate. When the sphericity of the erodent particles entering the cascade passage reaches 0.5856 or more, the erosion rate will be greatly reduced, thereby significantly alleviating the erosion damage of the blade. The results of this paper will provide theoretical basis and technical support for further understanding of the erosion mechanism of typical blade materials in dust-laden turbines.