The Experimental Study Of Ultrasonical Assisted Hard Turning Chip Shape And Surface Machining Quality

Metal cutting is a main and the most widely used processing method of the mechanical manufacturing industry. The hardened steel is even widely used to the base parts and components which have high requirements about the hardness and wear resistance, its processing method was often using the grinding in the past. But its application fields are limited because of its low grinding efficiency,high cost,polluting the environment badly and so on. The appearance of ultrasonical assisted hard turning solves the difficult problems mentioned above, ultrasonic vibration is introduced to common turning because it can reduce the effects of harmful vibration in cutting to the cutting process, and it can also reduce the cutting forces and cutting temperature effectively and get a good surface quality.This paper is committed to study on the ultrasonical assisted hard turning and common turning the 45 hardened steel. The influences of different cutting parameters(rotating speed of the machine,feed,cutting depth) on the surface roughness and its micro-topography are studied. The test results show that: compared with common turning, ultrasonical assisted hard turning has lower cutting force and cutting temperature and can get a better surface quality than common turning. Through the experiments and neural network modeling about the cutting processes of two different cutting conditions, the machined surface roughness can be predicted under different cutting conditions. Meanwhile, the surface roughness and surface micro-topography can also be observed under different cutting parameters by measuring and observing tools. In the main purpose of getting a good surface quality, obtain the optimized cutting parameters fitting for the ultrasonic vibration turning and common turning by optimizing the cutting parameters. Meanwhile we research and analysis the chip shapes under two different cutting conditions. The chip's formation process of ultrasonic vibration turning is more stable than common turning under the the same cutting parameters, and the obtained chip shapes are more regular. It can obtain better chip shapes and the chip shapes are the reflection of good or bad of the surface quality, that is ultrasonic vibration turning can get a better surface quality. Selecting the best parameters finally, it is an important way to increase productivity,achieve the lowest cost and get the maximum profits.