The Simulation Research On The Cutting Force Variation In Ultrasonic Assisted Turning

The ultrasound assisted turning technology is a new type of cutting technology which exert small amplitude and high frequency vibration on the tool, the technology makes the random vibration of the tool into a stable regular vibration, the cutting tool and the work piece generate periodic separation to reduce the contact time between the tool and he work piece surface, at the same time, it reduces the cutting force of cutting area, slows down the speed of the damage to tool, reduces the production cost, improves the processing quality and productivity of the work piece so ultrasound assisted turning technology has been widely applied in the field of scientific research.This paper is supported by Natural Science Foundation of Chongqing "Research for cutting force variation law and its impact on machining performance in ultrasonic assisted turning processing",,and conducts a series of simulation research for rule of cutting force during ultrasonic assisted turning.Firstly, the paper studies the theory of ultrasonic vibration turning technology in detail, and analyzes the effect of instantaneous cutting force in machining process combining with the principle of ultrasonic vibration turning, furthermore, the paper deduces the functional relationship between the amplitude, frequency, cutting speed and the cutting force,In order to study the impact of different frequency, amplitude, and the average cutting speed on cutting force, the paper uses the MATLAB simulation software for the numerical simulation.Secondly, this article adopts ANS YS software to establish finite element model of the ultrasonic vibration turning, and obtains the curve of instantaneous cutting force and equivalent stress nephogram, analyzes the separation process of cutting tool and work piece, Also simulates the instantaneous cutting force curve for conventional turning under the same condition, the results show that under the same condition, the cutting force produced by the ultrasonic assisted turning is much smaller than ordinary turning’s.Finally, in order to study the influence of different cutting speed, ultrasound frequency and amplitude of the ultrasonic turning instantaneous on the cutting force, the paper conducts a series of simulation experiment, and results show that:(1) As the cutting speed becomes larger, the cutting force generated by the ultrasonic vibration cutting also increases, and the average cutting force also increases, while cutting speed reaches the critical speed, the ultrasonic vibration cutting is close to the ordinary turning.(2) As the amplitude increases, the cutting forces generated by the tool cutting the work piece is reduced, the average cutting force is also decreased, experimental analysis shows that the influence of the amplitude on the cutting force of ultrasonic cutting turning is small.(3) When the frequency of ultrasonic vibrations is small, its peak changes of cutting force is not obvious; But when the frequency increases to 55KHz, the peak cutting force significantly changes according to the sinusoidal law, when the vibration frequency is small, the average cutting force value change is not obvious, but when the frequency is more than 45KHz, the average cutting force decreases significantly.