難削材切削時に発生する係数励振振動の研究

抄録

In this paper, the parametric vibration in machining of hard cutting metals is investigated. The vibration of this type restricts machining efficiency and accuracy conspicuously. The mechanism of vibration seems complex because of possible interactions among multiple mechanisms that cause the vibration. There have been few research activities conducted with regard to this phenomenon and applicable methods for suppression have not yet been established. Thus the parametric instability is predicted by theoretical analysis. Turning tests have been carried out for confirmation of the stability thresholds by machining of hard cutting metals. The results thus obtained art as follows : (1) There are natural frequency component and components of the chip formation in the parametric vibration. (2) The theoretical analysis for predicting the conditions of parametric instability were verified by good agreement with the results of the cutting test. (3) Parametric vibration of this type has the remarkable characteristics of low-and high-speed stabilities. (4) The regenerative vibration is excited frequently mingling with this parametric vibration.