单颗磨粒高速磨削镍基高温合金机理研究-机械制造及其自动化专业论文.docxVIP

南京航空航天大学硕士学位论文 南京航空航天大学硕士学位论文 单颗磨粒高速磨削镍基高温合金机理研究 单颗磨粒高速磨削镍基高温合金机理研究 I I II II 摘 要 镍基高温合金因其优异的力学性能被广泛应用于航空航天、船舶、化工等领域，然而它的 切削加工性极差，属于典型的难加工材料。近年来，高速磨削技术因其诸多优势得到了大力发 展，这为镍基高温合金的高效加工提供了新途径。但是，关于镍基高温合金的高速磨削机理仍 缺乏深入研究，难以指导实际磨削过程，导致其磨削效率低、加工质量稳定性差、工具寿命短。 作为砂轮磨削过程的一种简化模型，单颗磨粒磨削是探讨复杂磨削机理的有效方法。为此，针 对现有单颗磨粒磨削研究现状，本文设计了新的单颗磨粒磨削试验方案，在此基础上，对高速 超高速磨削镍基高温合金的材料去除机理进行了系统研究。开展的主要工作包括： （1）在理论分析单颗磨粒磨削轨迹的基础上，设计了符合实际磨削过程的单颗磨粒运动轨 迹，研制了单颗磨粒高速磨削试验装置。 （2）针对镍基高温合金 GH4169 开展了磨削速度为 80~150 m/s 的单颗磨粒高速超高速磨 削试验；对磨屑和工件表面磨痕的微观形貌进行了分析，并与普通磨削速度进行了对比；测试 了单颗磨粒磨削力，探讨了相同单颗磨粒切厚条件下，磨削速度对单颗磨粒磨削力的影响规律。 （3）深入分析了高速磨削镍基高温合金 GH4169 的成屑机理，并采用有限元仿真方法研究 了 GH4169 合金磨屑的形成过程，以及磨削速度对磨屑形态、磨削力和磨削温度的影响。在此 基础上，对磨削速度为 200~500 m/s 的超高速磨削 GH4169 合金磨屑形态进行了预测，同时对 其形成机理进行了探讨。 关键词：镍基高温合金，高速磨削，单颗磨粒，磨屑形貌，磨削力，有限元模拟 ABSTRACT Nickel superalloy has been widely used in aerospace, shipbuilding and chemical industry owing to its excellent mechanical performance. However, nickel superalloy is a typical of difficult-to-cut materials. In recent years, high speed grinding technology has been developed rapidly because it has many advantages. This provides a new way for grinding nickel superalloy. However, the high speed grinding mechanism has not been researched deeply, which leads to low grinding efficiency, poor stability of processing quality and short wheel life in the high speed grinding process. As a simplified model of the grinding, the grinding technique with single abrasive grain is an effective way to explore the mechanism of the complex grinding. Based on the disadvantages of single abrasive grain grinding experiments in the previous research, a new program of single grain grinding test is proposed and carried out in this paper. High speed and ultra high speed grinding mechanism of nickel superalloy with single grain is investigated. The main research work is described as follows: Based on the theoretical analysis of the single grain trace in grinding, the path of the single grain which accorded with the actual grinding trace has bee