大粒径磨料作用下高铝砖气固冲蚀磨损的“粒径效应”

Particle Size Effects on Gas Solid Erosion Wear of High Alumina Bricks Impacted by Abrasives with Large Particle Size

以平均粒径分别为0.28 mm、0.40 mm、0.52 mm、0.80 mm的棕刚玉为磨料对I等高铝砖进行常温垂直气固冲蚀磨损试验,对磨料和靶材冲后表面进行扫描电镜显微结构分析,在宽粒径范围内研究磨料粒径对靶材耐磨性与冲蚀机制的影响。借助ANSYS/LS-NYNA软件建立多粒子冲蚀模型,分析不同磨料粒径下的冲蚀行为。结果表明:I等高铝砖出现"粒径效应",临界粒径0.40 mm;靶材最大等效应力随磨料粒径的增加而增加;平均粒径≥0.40mm时磨料发生破碎,0.28 mm、0.40 mm、0.80 mm磨料冲蚀下靶材的主要冲蚀机制分别是基质和骨料微切削、基质和骨料断裂、缺陷处断裂。

In order to study the effects of particle size with a wide range on erosion wear resistance performance and erosion wear mechanisms of targets,gas solid erosion tests were carried out with grade I high alumina bricks impacted vertically by brown fused alumina abrasives at room temperature,whose mean particle size were respectively 0.28 mm,0.40 mm,0.52 mm,and 0.80 mm,and microstructure on the worn surface of abrasives and targets were analyzed using scanning election microscope.Erosion models impacted by single and multiple particles were proposed to analysis the erosion behavior with different erodent particle size using ANSYS/LS-DYNA software.The results show that ＂ Particle size effects＂ exist in grade I high alumina bricks,whose critical particle size is 0.40 mm.Maximum effective stresses of targets are increased with an increase in the particle size.Abrasives whose particle size is larger than 0.40 mm have been broken after the erosion process.The primary erosion wear mechanisms impacted by abrasives with particle size of 0.28 mm,0.40 mm and 0.80 mm are micro-cutting of matrix and aggregates,fracture of matrix and aggregates,and fracture of defects,respectively.