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An increase in bone-implant contact and an increase in surface hydrophilicity are the two important factors involved in improving osseointegration. Therefore, three-dimensional elliptical vibration turning method is applied to increase the hydrophilicity of titanium surface by the generation of hierarchical nano- and micro-textures. That being the case, face turning process at different cutting conditions is carried out in this research. Surface roughness and the contact angle of water drops with machined surfaces were selected to be measured for the analysis of surface hydrophilicity. The results show that an additional surface area can be achieved by the generation of micro- or nano-textures, resulting in a lower contact angle. Furthermore, intermittent movement of cutting tool in vibration cutting causes the process to be more stable, achieving the desired range of surface roughness. [ABSTRACT FROM AUTHOR]

Highlights • Analytical model of ultrasonic burnishing force has been developed. • Effect of ultrasonic vibration has been included. • Effect of surface elastic recovery has been included. • The results of analytical model were in line with experimental measurements. Abstract In our recently published work i.e. Teimouri et al. [25], mechanic of forces acting during burnishing process has been identified and fully discussed. The process was modeled based on slab method theorem and effect of burnishing parameters on horizontal and vertical forces were identified. However, the present work is an analytical approach to find effect of ultrasonic vibration parameters and pass number considering elastic rebound of work surface. In the proposed methodology effect of different parameters such as feed rate, ball diameter, depth of burnishing, vibration amplitude and pass number on the burnishing force. The comparison with experimental results allows to affirm that the model is a useful tool to predict the value of resultant burnishing force. [ABSTRACT FROM AUTHOR]

In the present work, experimental study was carried out to enhance the surface properties of aluminum 6061 and AISI 1045 steel plates by ultrasonic-assisted ball burnishing process. Full factorial experimental design was utilized here to find the effect of ultrasonic vibration, feed rate, and pass number on surface roughness and hardness. The results were discussed according to interaction effect of process factors for different material. It is found from the results that for conventional burnishing process, the highest surface hardness is attained at 5000 mm/min feed rate and 5 pass number, while for ultrasonic-assisted burnishing, the highest hardness is attained at 1000 mm/min feed rate and 5 pass number. On the other hand, it is found from the results that exerting ultrasonic vibration significantly enhances the hardness value and hardened depth. Also, it is found that irrespective of type of operation and material, increase in feed rate causes higher roughness, whereas increase in pass number causes reduction in roughness. Furthermore, surface roughness of ultrasonic-assisted burnishing is lower than that of conventional burnishing process. This enhancement is due to the association of both static and dynamic loading in ultrasonic-assisted burnishing process that causes microstructure modification and limits the elastic recovery of the surface. [ABSTRACT FROM AUTHOR]

High quality of machined surfaces is an important requirement in production industries. Therefore, different methods such as ultrasonic vibrations are implemented to improve this parameter. In this study, it is tried to specify some of effective parameters on surface improvement in ultrasonicassisted turning. Accordingly, a series of experiments in the way of conventional and vibratory turning are conducted where surface roughness and surface topography are evaluated as main objectives of this work. Furthermore, analysis of tool wear and radial displacement of tool and workpiece are carried out for explanation of surface enhancement in vibratory turning. As a result, it is shown that generated typical peaks and valleys in conventional turning are flattened and reduced in vibratory turning which is explained by existence of lower radial force. [ABSTRACT FROM AUTHOR]

Conventional drilling (CD) which is known by two constant rotary and linear motions causes some problems in drilling of materials such as high thrust force, poor surface quality, and rapid tool wear. To get rid of these problems or at least minimize them, a promising technology has been employed in the recent years, where vibrations usually with low amplitude and high frequency are applied to the direction of feed motion results in a time-dependent velocity between drill tip and workpiece. This paper focuses on the design of a vibratory tool following by experimental and numerical approaches to study the influence of longitudinal ultrasonic vibrations on drilling of aluminum alloy 7075. Experimental part is a comprehensive exercise to design, fabricate, and test a system equipped with different instruments to work in desired conditions. Experimental results are supported by a finite element method to better comprehend what is happening in cutting process when ultrasonic vibrations are added. The achieved results prove that using ultrasonic-assisted drilling (UAD), the machining ability of drilled aluminum workpiece can enhance significantly. Improvement of up to 40% for drill circularity and a reduction of up to 37% in thrust force were achieved. [ABSTRACT FROM AUTHOR]

In this study, influence of added linear vibration of cutting tool on the performance of rotary turning of AISI 4140 steel is investigated. Experimental tests are carried out at different cutting and tool rotary speeds by using special equipment for ultrasonic assisted rotary turning. The results of surface roughness, cutting force, and tool wear obtained during vibratory-rotary cutting are compared by the values of conventional and rotary turning. At the end, it is shown that lower displacement of workpiece in the radial direction, decrease of tool rake angle, and producing cooling cycle during disengagement time in vibration cutting cause lower wear distribution along the circumference of cutting tool. As a consequence to that, a significant reduction in surface roughness and cutting force is observed compared to the conventional and rotary turning. Besides, effect of variations in tool rotary and cutting speeds on output parameters are evaluated. [ABSTRACT FROM AUTHOR]

Studying the effect of longitudinal ultrasonic vibrations on the performance of incremental forming process of aluminum-1050 sheet is the main purpose of this paper. In this new technique, ultrasonic vibrations with high frequency and low amplitude are axially added to the movement of forming tool. To fulfill this purpose, a system was carefully devised. This system consists of different parts including a mechanism attached into the chuck of CNC machine to give rotary motion and also sent ultrasonic power to the vibratory tool. Straight groove test was performed, and various parameters including forming force and sheet formability were investigated in both conventional and ultrasonic-assisted incremental forming process. The achieved results show that ultrasonic assistance can increase formability and decrease forming force significantly. [ABSTRACT FROM AUTHOR]

Beside beneficial aspects of friction stir welding such as solid-state joining process, no melting, no recasting, etc., there are some disadvantages like considerable axial forging force especially for high-strength materials. Researchers have developed several innovative ideas to diminish the process problems. In the present study, to investigate the effect of bending vibrations, an ultrasonic vibratory tool of friction stir welding, in bending mode, has been designed and manufactured. Firstly, the vibratory tool was designed for the operating resonance frequency of 20 KHz in ABAQUS software. This tool consists of transducer, horn, and welding tool. Using the optimal dimensions achieved from the modal analysis, the FSW tool has been manufactured. Then, experimental investigations verify the validity of the tool design process, such as clamping flange position, resonance frequency, and so on. The friction stir welding of aluminum Al6061 and Teflon plates has been done with lathe machine. FSW-assisted ultrasonic vibrations in bending mode show some advantages in comparing with linear mode, such as decreased tool length and increased efficiency of vibrational energy transferring to the tool tip. Finally, with respect to the indicated improvements, reduction and rise of welding forces and temperature have been observed, respectively. [ABSTRACT FROM AUTHOR]