镗削碳纤维复合材料时切削用量对切削力及孔出口撕裂的影响

采用PCD刀具对碳纤维复合材料(CFRP)进行了镗削加工试验,分析了切削用量对切削力、孔出口撕裂因子(撕裂值与孔直径的比值)的影响规律.试验结果表明,三向切削力随背吃刀量、进给量、切削速率的增大而增大.经分析认为,切削速率的增大引起待加工材料的屈服应力增大.由于刀尖圆弧半径较大,试验中出现背向力大于主切削力的现象；撕裂因子与背吃刀量基本无关；进给量与撕裂因子呈线性正相关；当切削速率增大时撕裂因子呈减小趋势,并且减小到一定程度后基本不变；采用PCD刀具镗削加工该材料能够有效地减小孔出口撕裂程度.

Influence of Cutting Parameters on Cutting Forcesand Hole Exit Tear in Boring CFRP

In this paper, some experiments were carried out by using PCD tool to bore carbon fiber reinforced
plastics (CFRP) and the influence of cutting parameters on cutting force and hole exit tear factor(the ratio of tear size
and hole diameter) was analyzed. The testing results showed that 3-D components of cutting forces increase along
with the increasing of the cutting depth, feed rate and cutting speed. It is indicated that the raise of cutting speed results
in the increasing of yield-stress of the material. Large corner radius causes the highest radial force, followed by
the main cutting force and axial force;Tear factor is almost independent of cutting depth, but there is a linear positive
correlation between the factor and feed rate. When increasing the cutting speed the value of tear factor shows a tendency
to decrease and then kept essentially constant. Boring CFRP using PCD tool can effectively reduce tear degree of
hole exit.