碳纤维复合材料钻削温度对孔壁微观形貌的影响分析研究

摘要

In order to solve the problem that the surface of hole wall is greatly affected by the high gradient temperature field formed in drilling process, it describes the thermal expansion coefficient of carbon fiber and resin matrix in carbon fiber reinforced composites.Using the embedded artificial thermocouple method, it tests the temperature of the carbide bit in drilling CFRP, obtains the heat of drilling distribution from the grinding of the cutting edge and workpiece material and the friction between the flank and the machined surface.As the feed rate increases, the tool flank surface temperature tends to decrease.When the drilling temperature is 249.38℃, which exceeds the glass-transition temperature, no cauterization occurres on the surface of the hole wall, and high spindle speed results in high cutting temperature at the cutting region.It applies the softening of the resin matrix to the fracture of the carbon fiber edge, decrease the roughness.%为解决碳纤维复合材料中因碳纤维和树脂基体的热膨胀系数相差较大,受钻削时所形成的高梯度温度场影响而显著降低孔壁表面质量的难题,采用嵌入式人工热电偶的方法对钻削碳纤维复合材料的硬质合金钻头进行测温试验,试验结果显示:钻削热主要来源于钻头横刃与工件材料的研磨和后刀面与已加工表面的摩擦,随着进给量增大,刀具后刀面的温度逐渐降低;在钻削温度为249.38℃时(超过环氧树脂的玻璃化转变温度),孔壁表面并未发生烧灼现象;随着切削区域温度的升高,树脂基体软化重构涂覆在断裂的碳纤维刃口上,从而导致其孔壁粗糙度下降.研究表明通过控制切削参数可以得到适当的钻削温度,可有效提高钻削的孔壁质量.