GFRP低频轴向振动制孔的钻削力特性和套料钻磨损分析

GFRP的套孔钻削过程中极易产生分层、撕裂等加工损伤，其与轴向钻削力直接相关。为提高GFRP的制孔质量，采用新型金刚石薄壁套料钻，结合低频轴向振动加工技术，建立单颗磨粒的运动学模型和动力学模型，试验研究GFRP制孔中的轴向力变化规律，并对套料钻的烧焦概率、自动落料率进行分析。结果表明：对比常规钻削，低频振动钻削时的瞬时进给量和轴向力比常规钻削时的大，且随着振幅的增加，轴向力也随之增大；低频振动钻削和常规钻削时的轴向力皆随进给速度的增加而增大，随主轴转速的升高而降低。同时，低频振动钻削时磨粒间断性地参与钻削，大大降低了套料钻的烧焦概率，提高了其自动落料率，自动落料率高达88.24%，可实现GFRP的连续批量制孔。

Analysis of drilling force characteristics and trepanning tool wear during GFRP low frequency axial vibration drilling hole

The processing damages such as delamination and tearing were easily produced during the drilling of the sleeve holes of GFRP, which were directly related to the axial drilling force. In order to improve the quality of GFRP hole-making, a new diamond thin-wall trepanning tool was adopted; and combined with the low-frequency axial vibration machining technology, the kinematic model and the dynamic model of single abrasive particle were established. The variation law of axial force in GFRP hole-making was experimentally studied. The burning probability and the automatic blanking rate of trepanning tool were analyzed. The results show that the instantaneous feed rate and the axial force of low-frequency vibration drilling are larger than that of conventional drilling. Besides, the axial force increases with the increase of amplitude, and the axial forces of the low-frequency vibration drilling and the conventional drilling increase with the increase of feed speed and decrease with the increase of spindle speed. At the same time, the abrasive particles participate in drilling intermittently, which greatly reduces the burning probability of the trepanning drill and improves its automatic blanking rate. The automatic blanking rate during low-frequency vibration drilling is up to 88.24%, which can realize the continuous batch hole-making of GFRP.