难加工材料孔超硬磨料高速高效珩磨技术的基础研究

To solve the problem of low efficiency, poor stability of surface quality and drastic tool wear in honing of difficult-to-machine materials holes, high speed and efficiency honing technology is put forward by integrating the advantages of superhard abrasive and high speed honing. Aiming at the issues of foundational research for high speed honing technology of the difficult-to-machine materials holes with superhard abrasive tools, this research will be carried out in the following aspects. Firstly, the influence of speed on the materials removal mechanism and formation mechanism of honed surface is to be theoretically analyzed. Thereafter the electroplated superhard abrasive honing tool which is suitable for high speed and efficiency honing of difficult-to-machine materials will be designed and manufactured. Meanwhile, the variation law of the honing tool topography will be explored and the mapping relationship between the tool topography characteristics and honed surface quality of difficult-to-machine materials holes will be investigated. The superalloy hole will be honed with the electroplated CBN tool and optimum conditions. This research is supposed not only to provide theoretical basis for improving both the efficiency and stability of precision machining of difficult-to-machine materials holes, but also to offer parameter references for high speed and efficiency honing with superhard abrasive tool in engineering application.

课题针对难加工材料孔珩磨时效率低、表面质量不易控制、工具损耗快等问题，提出利用超硬磨料工具和高速珩磨工艺二者的集成优势，开展难加工材料孔超硬磨料高速高效珩磨技术的基础研究。深入研究难加工材料孔高速高效珩磨加工机理，探讨速度效应对材料去除及加工表面形成的影响机制,阐明高速条件下难加工材料孔珩磨既能保证加工精度和表面质量又能大幅提高加工效率的本质原因；在此基础上，依据难加工材料孔高速高效珩磨加工要求与用量条件优化设计工具；阐明工具地貌演变行为及其对加工质量的影响规律，指导用量条件优化，实现工件-工具-工艺的合理匹配；采用优化的电镀CBN珩磨工具和工艺进行典型难加工材料（高温合金）孔珩磨验证试验。课题的研究可为实现难加工材料孔的高效、高精和表面质量优异的精密加工提供理论基础，并为超硬磨料高速高效珩磨技术的工程应用提供参数依据。

为实现难加工材料孔的高效精密加工，本项目开展了难加工材料孔超硬磨料高速高效珩磨技术基础研究。采用仿真结合试验的方法对珩磨加工的材料去除机制进行研究，结果表明珩磨过程中连续切削与断续切削共存，磨粒在网纹交叉点处的磨削力会突然降低，断续切削时磨粒行经交叉点处时磨屑会发生“失稳”，继而从工件表面脱离。研究了工艺参数对珩磨表面质量和材料去除率的影响。普通珩磨条件下，主轴转速和往复速度对表面粗糙度影响不显著，油石粒径的影响最显著，其次是每往复进给量，随着粒径和每往复进给量的增大，表面越来越粗糙，网纹沟槽的深度和宽度也逐渐增加。每往复进给量、油石粒径对材料去除率影响非常显著，往复速度影响显著，且材料去除率与三者之间均呈现正相关关系；主轴转速对材料去除率影响不显著。高速珩磨条件下，主轴转速、涨刀行程和涨刀时间对表面粗糙度Ra影响显著，往复速度对Ra影响不显著；主轴转速和涨刀时间对Rz影响显著，往复速度和涨刀行程对Rz影响不显著；表面粗糙度随着主轴转速的提高和涨刀时间的增加而下降，随涨刀行程的增大而增大。主轴转速、涨刀行程和涨刀时间对材料去除率影响显著，往复速度影响不显著；随着主轴转速的提高和涨刀行程的增大，材料去除率增大；随涨刀时间增大材料去除率减小。珩磨工件表层微观金相组织都未发现明显变化，未发现磨削变质层，珩磨加工未引起新的表层加工硬化。基于Matlab建立了珩磨加工表面质量、工具特征及工艺参数的关联模型，并进行了高速珩磨试验验证；采用响应曲面法进行了珩磨工艺参数的优选。最后，优化设计了电镀珩磨工具及其制备工艺，采用自研的电镀CBN珩磨工具结合优化的珩磨工艺参数，实现了难加工材料模拟件和航空发动机燃油喷嘴活门孔的高速珩磨加工。