In this paper an innovative VIBRATION rotary tool was designed and manufactured. VIBRATION TURNING tool is a compound of TURNING rotary tool and ultrasonic assistant TURNING. In this tool, an ultrasonic wave generator with power equal to 20 KHz transducer that has a rotational motion during the process was used. For tool VIBRATION, a stainless horn with resonance frequency equal to 20618 Hz, were designed and manufactured. Round insert with 10 millimeter diameter were used. One of the most important key points in this setup is that the simultaneous rotation and VIBRATION has to be achieved. For rotational motion a motor power and a rack and pinion were used. Also a structure with ability to mount on TURNING machine were designed and manufactured. Cutting force and surface roughness for each experiment were measured and compared with data collected from conventional rotary tool on 7075 aluminum material. Results shows that ultrasonic VIBRATION cause decreasing in cutting tools and surface roughness, tremendously.

Chattering is a kind of self-excited VIBRATION encountered in different machining processes such as milling and TURNING. This type of self-excited VIBRATION rapidly develops after commencement and destabilizes the whole process. This phenomenon leads to, among other issues, increased noise, wavy surface finishes, discontinuous chips, and failure in the tool or machine parts. The depth of cut is the main parameter in the occurrence of chattering in machining processes. Avoiding the critical depth of cut ensures the stability of the process. Process modeling is a way to obtain the critical depth of cut. The VIBRATION-ASSISTED TURNING process has many advantages and is of a different nature than the conventional machining. In this paper, the VIBRATION-ASSISTED TURNING process is modeled and numerically solved and the critical depth of cut is obtained. Validation of the results is performed using experimental data and comparison with conventional machining. In the VIBRATION-ASSISTED TURNING process, higher stability is obtained with lower ratios of cutting duration to the total VIBRATION period.This ratio is directly proportional to VIBRATION frequency and amplitude and is inversely proportional to the cutting speed.

VIBRATION cutting (VC), elliptical VIBRATION cutting (EVC) and ordinary cutting (OC) of In 738 work-pieces have been experimentally investigated in the present research. The experiments were carried out by using single crystal diamond tool and ultra-precision CNC lathe. VIBRATION frequency is 36.16 KHz and the amplitude is 4 mm. The influence of various cutting parameters including cutting speed, feedrate, VIBRATION amplitude and phase angle on the cutting force, surface roughness and tool life have been studied and the results have been compared. The results indicate that the cutting force in EVC is much less than the two other processes. The surface roughness in both the cutting and feed directions was also less than those in other processes.

VIBRATION cutting (VC), elliptical VIBRATION cutting (EVC) and conventional cutting (OC) of Ud500 work-pieces have been experimentally investigated in the present research. The experiments were carried out by using single crystal diamond tool and ultra-precision CNC lathe. The influence of various cutting parameters including cutting speed, feed-rate, VIBRATION amplitude and phase angle on the cutting force, surface roughness and tool life have been studied and the results obtained in the aforementioned processes have been compared. The results indicate that the cutting force in EVC is much less than the two other processes. The surface roughness in both the cutting and feed directions was also less than those in other processes. In addition, far longer tool life was observed in EVC compared with the two other processes.

Since the invention of ultrasonic VIBRATION ASSISTED TURNING, this process has been widely considered and investigated. The reason for this consideration is the unique features of this process, which include reducing machining forces, reducing wear, and friction, increasing the tool life, creating periodic cutting conditions, increasing the machinability of difficult-to-cut material, increasing the surface quality, creating a hierarchical structure (micro-nano textures) on the surface and so on. Different methods have hitherto been used to apply ultrasonic VIBRATION to the tip of the tool during the TURNING process. In this research, a unique horn has been designed and constructed to convert linear VIBRATIONs of piezoelectrics to threedimensional VIBRATIONs (longitudinal VIBRATIONs along the z axis, bending VIBRATIONs around the x axis, and bending VIBRATIONs around the y axis). The advantage of this ultrasonic machining tool compared with other similar tools is that in most other tools, it is only possible to apply one-dimensional (linear) and two-dimensional (elliptical) VIBRATIONs, while this tool can create three-dimensional VIBRATIONs. Additionally, since the nature of the designed horn can lead to the creation of three-dimensional VIBRATIONs, there is no need for piezoelectric half-rings (which are stimulated by 180 phase difference) to create bending VIBRATIONs around the x and y axes. The reduction of costs as well as simplicity of applying three-dimensional VIBRATIONs in this new method can play an important role in industrializing the process of three-dimensional ultrasonic VIBRATION ASSISTED TURNING.

The spring-back of a work-piece during machining operation causes dimensional error of the work-piece. In the present study, the spring-back of work-piece in ultrasonic-VIBRATION ASSISTED TURNING and conventional TURNING has been modeled. It is illustrated that the reaction of the work-piece in high frequency VIBRATION cutting is similar to a static behavior, whereas the spring-back in this process is theoretically and experimentally smaller than the conventional cutting leading to smaller error. A method has also been proposed to obtain the errors caused by rigid assumption of the spindle assembly used for correction of the results.

A machining force model for ultrasonic VIBRATION-ASSISTED TURNING (UAT) has been developed in the present study. For this purpose, extensive full-factorial experiments were carried out and the results were analyzed statistically. Various influential parameters, such as cutting speed, feed rate, depth of cut, and ultrasonic VIBRATION amplitude were taken into account. The proposed model was selected from among four different regression models. The condition for the robustness of the proposed model was then investigated. Several experiments were also carried out on conventional TURNING and the results were analyzed and compared with those obtained during ultrasonic VIBRATION-ASSISTED TURNING. It was shown that the quadratic polynomial model can better estimate the machining force. The latter experiment with a vibrating tool is unconditional and considerably lower than that created in conventional TURNING. The continuous chip being formed in UAT is partially responsible for more efficient machining (from the view point of ductile regime of machining) compared to conventional TURNING (CT).

The aim of present study is to investigate the kinematics of tool-workpiece’s relative movement in conventional and ultrasonic-VIBRATION ASSISTED TURNING (UAT). The kinematic analysis of UAT shows that the movement of cutting tool edge relative to the workpiece resulted from the cutting speed, feed speed and tool’s VIBRATION affects the lateral machined surface of workpiece and leaves a repeating pattern of crushed and toothed regions on it. This results in an increase in the surface hardness of the lateral machined surface in comparison with conventional TURNING (CT). A model of the toolworkpiece’s relative movement has first been developed in the present study. This model predicts a surface hardening effect for the lateral surface in UAT in comparison with CT. Several experiments were subsequently carried out employing a surface micro-hardness testing machine and an optical microscope to verify the predicted results.

In this paper, Ultrasonic ASSISTED cutting (UAT) process has been investigated. The cutting technique is among the advanced machining techniques which improve cutting capability of materials. Vibratory tool is made under longitudinal mode with 10 micron amplitude and 20 KHz frequency, in such a way that VIBRATION is applied in cutting speed direction. Experiment carried out on Al7075; using ultrasonic ASSISTED TURNING has lead to reduction in the cutting force, versus traditional cutting process. Moreover, further experiments were done aiming at investigating effective parameters in UAT machining process on Al7075 parts. These parameters include cutting speed, feed rate, depth of cut, and VIBRATION amplitude. Statistical analysis on the experiment results were carried out, and different mathematical models for forecasting cutting force and optimizing machining parameters are presented in order to achieve minimum cutting force. At the end, cutting forces were compared for two machining processes namely ultrasonic ASSISTED cutting (UAT) process, and traditional machining.