【摘要】 分析现有一种加热电阻模型的不合理性,针对切削区的变形特点,提出一种符合实际变形情况的加热电阻模型,从理论上建立该电阻三个组成部分与刀具角度、切削用量、变形系数等计算公式。根据加热回路的特点,提出一种对加热电阻的精确检测方法,结果表明,此电阻随切削深度、进给量的增大而减小,而随切削速度的增大而增大,验证了理论分析,进而建立了该电阻和切削用量三要素的经验公式。通过对加热电阻的检测可以判断切削用量的变化状况,进而实现对加热电流的自动调整。最后指出,在加热电阻的三个组成部分中,材料电阻和扩展电阻对改善材料的切削加工性起关键作用,而刀—屑接触电阻则会加剧前刀面的磨损。更多还原

【Abstract】 The irrationality of an existing heating resistance model is analyzed firstly.In view of the deformation characteristic of shear zone,a new heating resistance model coinciding with the real deformation state of shear zone is proposed.The relationship among the three components of this resistance and tool angle,cutting condition,deformation coefficient are studied theoretically and theoretic formula of heating resistance is obtained.Secondly,an accurate measurement method for this resistance is put forward according to the characteristic of heating circuit.The experiment results show that this resistance will decrease when cutting depth or feed is increased,while it will increase when cutting speed is increased,which are consistent with the theoretical analysis.An experiential formula for this resistance and the three factors of cutting condition is also obtained.Thirdly,it is pointed out that the variation of cutting condition can be detected by the variation of heating resistance,so heating current can be adjusted automatically according to the variation of this resistance.Finally,it is indicated that for the three components of heating resistance,the material resistance and spread resistance will improve the machining performance of workpiece material,while tool-chip touch resistance will aggravate the wear of rake face.更多还原