磨粒几何排列对 Inconel 718 磨抛的有限元仿真研究

目的 为了提高砂带磨抛镍基合金 Inconel 718 的表面精度,避免砂带上磨屑堆积等问题,针对砂带表面磨粒的顶端结构以及排列方式进行了分析,通过三维动力学仿真方法,研究磨抛过程中磨削力和磨屑的变化情况。 方法开展三种尖端类型磨粒和排列间距、倾角对 Inconel 718 的磨削机理研究,先分析尖端为点型、线型、面型的磨粒磨削过程,对比不同尖端类型磨粒的切屑形态与磨削力的大小,根据挑选出的点型尖端磨粒建立正四面体磨粒,利用该类型磨粒建立有序与无序的金刚石多磨粒模型,通过有限元软件分析磨粒水平和竖直方向上的间隙大小以及磨粒排布线倾角变化对磨削力和工件表面质量的影响。 结果 发现点型尖端磨粒产生的切屑呈碎屑状,更容易在多磨粒间排出,不易堵塞砂带,且在磨削过程中所受的磨削力更小;分析发现有序排列的磨粒类型具有很大的优势,能够提高工件表面精度,在工件表面产生大小均匀的沟槽,同时降低砂带受到的磨抛力小;发现磨削力大小会随着排布线倾角的增加呈现先增大后减小趋势。 通过与实验对比,发现磨屑的形状会随着水平方向间隙的增大而变化,呈现出由块状至带状到细长条状的变化规律,细长条状的磨屑更易从间隙中排出,从而达到降低磨抛力的效果。结论 采用点型尖端磨粒和合适的磨粒排布规律能够有效提高磨抛后的工件表面精度和促进磨屑的排出,为砂带的制造生产提供新的思路。

Finite Element Simulation Study of the Geometric Arrangement of Abrasive Grains on the Grinding of Inconel718

Objective To improve the surface precision of nickel-based alloy Inconel 718 during belt grinding andpolishing and to avoid issues such as abrasive grains accumulation on the belt an analysis was conducted on the topstructure and arrangement of abrasive grains on the belt surface. Through three-dimensional dynamic simulation thevariations in grinding force and abrasive debris during the grinding and polishing process were studied. Methods Threetypes of abrasive grain tip shapes and arrangement spacings as well as inclinations were investigated for their grindingmechanisms on Inconel 718. Initially the grinding processes of point line and surface-shaped abrasive grains wereanalyzed comparing the chip morphology and grinding force of different types of abrasive grains. Based on the selected multi-grain models were developed using this type of abrasive grain. Finite element software was used to analyze the effects of gap sizes in both horizontal and vertical directions and changes in abrasive grain arrangement line inclinations ongrinding force and workpiece surface quality. Results The results showed that the chip produced by point-type abrasigrve ains was fragmented making it easier to discharge between multiple abrasive grains and less likely to clog the belt while experiencing lower grinding forces during the grinding process. It was found that ordered arrangement of abrasivegrains had significant advantages improving workpiece surface precision creating uniformly sized grooves on theworkpiece surface and reducing the force exerted on the belt. It was also observed that the magnitude of grinding forceincreased and then decreased with the increase in arrangement line inclination. Through comparison with experiments itwas found that the shape of abrasive debris changes from block-like to strip-like to elongated strip-like as the horizontal gapincreases. Elongated strip-like debris is more easily discharged from the gap thus achieving the effect of reducingpolishing force. Conclusion The use of point-type abrasive grains and appropriate abrasive grain arrangement patterns caneffectively improve surface precision after grinding and polishing and promote the discharge of abrasive debris providingnew insights for the manufacturing and production of abrasive belts.