切削功耗变化视角下的刀具磨损监测方法

Tool Wear Monitoring Method based on Change of the Cutting Power Consumption

刀具磨损监测是机械加工领域关注的重点问题,基于机床功率变化的刀具磨损监测方法是当前主流的监测方法。对于微铣削加工而言,由于材料切削功率占机床总功率的比例极小,运用传统方法难以监测到机床功率在加工过程中因刀具磨损产生的变化。针对微铣刀具在加工过程中的磨损问题,本论文以切削功耗为基础提出了一种刀具磨损监测方法:文章从切削力做功的角度出发对材料切削功耗进行了建模,结合材料去除体积提出了单位功模型;在切削参数固定的条件下,从切向剪切力系数和切向犁切力系数两个方面分析了刀具磨损对单位功的影响;以小直径硬质合金立铣刀铣削铝合金7075为例开展了多次刀具磨损实验,并在实验过程中监测了单位功的变化趋势,通过将单位功的变化趋势与刀具磨损进行关联,验证了本文方法的可行性,证明了该方法可用于微铣削过程中的刀具磨损监测。

Tool wear monitoring is an important issue in the machining field,and the tool wear monitoring method that is based on the change of machine tool power has been widely studied.For the micro milling process,it is difficult to monitor the change of machine tool power caused by tool wear by traditional methods,because the ratio of material cutting power to machine total power is very small.This article proposes a new method to monitor the wear of the micro milling cutter based on the cutting power consumption.Based on the cutting force,the material cutting power consumption is modeled.Combined with the material removal volume,unit power consumption(UPC)model is established.When the cutting parameters are fixed,the influence of tool wear on UPC is analyzed from the perspective of tangential shearing force coefficient and tangential ploughing force coefficient.Several tool wear experiments are carried out by milling aluminum alloy 7075 with the cemented carbide end milling cutters,and the change trend of UPC is monitored.By correlating the change trend of UPC with the tool wear,it is proved that the proposed method can be used for tool wear monitoring in the micro milling process.