超声辅助磨削硬脆材料芯棒直径预测模型  

Prediction model of core rod diameter of hard and brittle material processed by ultrasonic assisted grinding

作　　者：董志刚[1] 段佳冬 康仁科[1] 朱祥龙[1] 郑非非[1] 

机构地区：[1]大连理工大学精密与特种加工教育部重点实验室,辽宁大连116024

出　　处：《光学精密工程》2017年第8期2106-2112,共7页Optics and Precision Engineering

基　　金：高档数控机床与基础制造装备国家科技重大专项(04专项)课题(2016ZX04002005);国家重点研发计划项目(2016YFB1102205);国家商用飞机制造工工程技术研究中心创新基金(COMAC-SFGS-2016-33239)

摘　　要：超声辅助磨削是一种套料芯棒加工方法,而硬脆材料在超声辅助磨削加工过程中的去除模式主要为脆性断裂,这将导致加工出的芯棒直径与砂轮内径之间存在尺寸误差。针对上述问题,通过分析超声辅助磨削加工中砂轮表面金刚石磨粒的运动轨迹,运用压痕断裂力学理论建立了超声辅助磨削芯棒的直径预测模型。该模型考虑了脆性材料断裂时产生的侧位裂纹扩展对芯棒直径的影响。通过对K9光学玻璃材料进行超声辅助套料试验对模型进行了标定和验证,接着研究了进给速度和转速对芯棒直径误差的影响规律。通过对比研究发现,模型计算结果与试验结果吻合较好,误差小于5%,验证了模型的有效性。试验结果表明,采用适当的低转速和大进给速度可以有效降低超声辅助磨削芯棒直径的尺寸误差。本文所建模型可为超声辅助磨削套料芯棒的砂轮选择提供理论指导。Ultrasonic assisted grinding is an effective way for trepanning the core rod, but the brittle fracture is the main manner to remove the hard and brittle materials during ultrasonic assisted grinding, leading to di- mension error between the rod diameter and the inner diameter of the grinding wheel. Aiming at the above problem, based on the theory of indentation fracture mechanics and the kinematic analysis of diamond grains on the grinding wheel, a prediction model of the rod diameter was established, during which the effects of the expansion of the lateral cracks on the rod diameter were considered at the same time. Subsequently, the model was calibrated and verified through the test of ultrasonic assisted trepanning of core rod of K9 optical glass. The effect of the feed and spindle speed on the rod diameter was studied. The comparison experiment indicates that the simulation results are in good agreement with the experimental results, and the error is within 5 %, which verifies the validity of the model. The experimental results show that the diameter error of the core rod can be reduced effectively with lower speed and higher feed rate during ultrasonic assisted grinding. The es tablished prediction model of the rod diameter can offer theoretical guidance to the selection of the grinding wheel for trepanning the core rod with ultrasonic assisted grinding.

关 键 词：硬脆材料 超声辅助磨削 直径预测 芯棒尺寸误差 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] TH691.9[自动化与计算机技术—计算机科学与技术]