【作者】 蓝善超；

【导师】 李文斌；

【作者基本信息】 太原理工大学 ， 机械制造及其自动化， 2012， 硕士

【摘要】 随着机械制造业的快速发展,发动机和液压泵得到了广泛地应用。发动机涡轮叶片根部和液压泵转子叶片根部分布着窄深槽结构。窄深槽是深宽比大于2,槽宽小于4mm的特殊结构。零件上窄深槽的加工质量很大程度上决定了零件质量。高精度窄深槽的制造一直是机械加工中的难题。传统的加工方法成本高、精度低,难以满足加工要求。电镀CBN (Cubic Boron Nitride)砂轮具有一系列优良性能,广泛运用于高精度窄深槽的加工,取得了良好的效果。磨粒粒度反映了磨粒尺寸的大小,它是砂轮的主要特性指标之一。磨粒尺寸直接影响着其顶锥角2θ及尖端钝圆半径rg两个参数的值,这两个参数描述了磨粒的锋利程度；磨削用量直接决定了磨削力、磨削温度、砂轮磨损以及加工质量等。本论文基于单颗粒磨削,研究了磨粒粒度和磨削用量对磨削力、磨削温度、砂轮磨损的影响。主要研究内容有：1)论述了磨削的基本原理,主要包括磨粒切削刃的形状及分布、磨削物理模型、砂轮与工件的接触弧长、单颗粒磨削的未变形磨屑厚度、磨削力、磨削温度、砂轮磨损。为后续的建模和仿真提供理论依据。2)分别建立了36#、46#、60#、80#的单颗CBN磨粒和工件的几何模型。将单颗CBN磨粒简化为带尖端钝圆的圆锥体、将工件简化为长方体,将单颗粒磨削简化为直线滑擦模型。介绍了有限元模拟仿真的关键技术,建立了工件的材料模型、切屑分离准则、材料断裂准则、网格划分准则、刀-屑接触摩擦模型以及磨损模型,并通过仿真验证了上述参数的正确性。3)针对不同粒度(36#、46#、60#、80#)的电镀CBN砂轮在淬硬轴承钢GCr15上磨削2×10mm的窄深槽的情况(磨削速度为40m/s、进给速度为5mm/s),应用DEFORM-3D软件对相应单颗CBN磨粒的磨削力、磨削温度以及磨损进行了仿真分析,结果表明：单颗CBN磨粒受到的磨削力、磨削温度以及磨损均随CBN磨粒粒度的减小而减小。4)针对电镀CBN砂轮(粒度为46#、进给速度为5mm/s)以不同的磨削速度(20m/s、30m/s、40m/s、50m/s)在淬硬轴承钢GCr15上磨削2X10mm的窄深槽的情况,应用DEFORM-3D软件对相应单颗CBN磨粒的磨削力、磨削温度以及磨损进行了仿真分析,结果表明：单颗CBN磨粒受到的磨削力随磨削速度的增大而减小,而磨削温度及磨损均随磨削速度的增大而增大。5)针对电镀CBN砂轮(粒度为46#、磨削速度为40m/s)以不同的进给速度(2mm/s,3mm/s,4mm/s,5mm/s)在淬硬轴承钢GCr15上磨削2×10mm的窄深槽的情况,应用DEFORM-3D软件对相应单颗CBN磨粒的磨削力、磨削温度以及磨损进行了仿真分析,结果表明：单颗CBN磨粒受到的磨削力、磨削温度以及磨损均随进给速度的增大而增大。更多还原

【Abstract】 With the rapid development of mechanical manufacturing industry, Engine and hydraulic pump are used widely. Narrow-and-deep slops are distributed in the root of engine turbine blades and hydraulic pump rotor blades. Narrow-and-deep slop is a special construction which depth-width ratio over2and width over4mm. The quality of narrow-and-deep slop greatly determines the quality of part. Machining narrow-and-deep slop with high accuracy is a difficult problem of mechanical processing. The traditional machining methods with weaknesses such as high cost、low accuracy and can’t meet requirement of machining. Because electroplated CBN grinding wheel possesses a series of excellent performance, it has been widely used in machining narrow-and-deep slop and obtained good results.The grain size reflects the dimension of grain, which is one of the main characteristic targets of electroplated CBN grinding wheel. Grain’s dimension directly effects on taper angle20and blunt round radius rg, so it will affect the sharpness of grain. Grinding parameters directly effect on grinding force、 grinding temperature、grinding wheel wear and machining quality. This paper mainly studies the influence of grain size and grinding parameters on grinding force、grinding temperature、grinding wheel wear based on single abrasive grain grinding. Main content as follow:1) The basic principle of grinding is discussed,which mainly include the shape and distribution of cutting edge、physical model of Grinding、contact arc between grinding wheel and workpiece、undeformed chip thickness、grinding force、grinding temperature、grinding wheel wear. It provides theoretical foundation for modeling and simulation.2) The geometrical model of workpiece and single CBN abrasive grains with size36#、46、60#、80#are built. CBN grains are simplified as cone shapes with blunt round radiusrg. Workpiece is simplified as cuboid. Straight sliding model is built. Key technology of simulation is introduced, the key parameters are confirmed, such as material model of workpiece、chip separation criterion、 Material fracture criterion、meshing、friction model of rake face and chip、model of wear. the key parameters are proved to be reasonable by simulate results.3) It aimed at that narrow-and-deep slop with dimension of2×10is machined on GCr15(grinding speed40m/s、feed speed5mm/s)by CBN grinding wheel with different size(36#、46#、60#、80#).The grinding force、grinding temperature、grinding wheel wear of single CBN abrasive grain is simulated and analyzed using software DEFORM-3D.The results show that:with the size decreasing,the grinding force、grinding temperature and grinding wheel wear of single abrasive grain decrease.4) It aimed at that narrow-and-deep slop with dimension of2×10is machined on GCr15(size46#、feed speed5mm/s) by CBN grinding wheel with different grinding speed(20m/s、30m/s、40m/s、50m/s).The grinding force、 grinding temperature、grinding wheel wear of single CBN abrasive grain is simulated and analyzed using software DEFORM-3D.The results show:with the grinding speed increasing, the grinding force decrease,while the grinding temperature and the grinding wheel wear of single abrasive grain increase.5) It aimed at that narrow-and-deep slop with dimension of2×10is machined on GCr15(size46#、grinding speed40m/s) by CBN grinding wheel with different feed speed(2mm/s、3mm/s、4mm/s、5mm/s).The grinding force、 grinding temperature、grinding wheel wear of single CBN abrasive grain is simulated and analyzed using software DEFORM-3D.The results show that: with the feed speed increasing, the grinding force、the grinding temperature and the grinding wheel wear of single abrasive grain increase.更多还原