1Cr9Mo钢高速气-固两相流冲蚀磨损

采用自制的激波驱动气-固两相流冲蚀磨损试验装置,选取SiO2、Al2O3和SiC颗粒,对煤化工常用材料1Cr9Mo钢进行高速气-固两相流冲蚀磨损试验研究.结合试件表面冲蚀磨损形貌,分析冲击速度、冲击角度、颗粒硬度、颗粒粒径、试件温度等因素对材料的冲蚀磨损率的影响.结果表明:在20 ℃和400℃下,1Cr9Mo钢的最大冲蚀磨损率均出现在15°～25°的冲蚀角之间,体现出典型塑性材料的冲蚀磨损特征;低角度冲蚀时磨损机理以颗粒的切削作用为主,高角度冲蚀时颗粒垂直撞击材料表面产生凹坑并致使凹坑周围的片状物碎屑从材料表面剥离;试件冲击速度指数在2.3 ～3.2范围内,磨损率受颗粒硬度影响较大;在相同冲蚀条件下,硬度较高的Al2O3和SiC颗粒对试件的磨损率比SiO2颗粒高一个数量级;磨损率随颗粒粒径的增大呈现先递增后下降的趋势;在400℃时SiO2颗粒对试件的冲蚀磨损率明显提高,磨损率最大值约为20℃时的3倍.

High-speed gas-solid two-phase flow erosion of 1Cr9Mo alloy

A self-made gas-solid erosion testing apparatus driven by shock wave was used to investigate the wear properties of 1Cr9Mo steel commonly used as manufacturing materials in the coal chemical industry,and SiO2,Al2 O3 and SiC particles were chosen as erosive particles.Combined with the surface morphology analysis of eroded specimens,high-speed erosion wear characteristics were studied under different conditions involving impact velocity,impact angle,particle hardness,particle size,and specimen temperature.The results show that when the temperature is 20 ℃ and 400 ℃,the erosion rate of 1Cr9Mo steel reaches its maximum value within an impact angle range of 15° to 25°,and the wear properties are characterized as ductile metal.At low impact angles the cutting of parti cles is the main mechanism;but at large impact angles the erosion mechanism is the exfoliation of platelets around the pits from the material surface,which is produced by the vertical impact of particles to the material surface.When the velocity exponent of 1Cr9Mo steel ranges from 2.3 to 3.2,the erosion rate is much dependent on particle hardness.Under the same erosion conditions,the erosion rate caused by Al2 O3 and SiC particles is an order of magnitude higher than that caused by SiO2 particles for they have higher hardness values.With the increase of particle size,the erosion rate increases first and then falls.The erosion rate caused by SiO2 particles at 400 ℃ increases significantly,and the maximum erosion rate is 3 times as large as that at 20 ℃.