ORIGINAL ARTICLE Analysis of linear vibration in rotary turning of AISI 4140 steel Saeid Amini 1 & Mohsen Aghaei 1 & Mohammad Lotfi 1 & Emad Hakimi 1 Received: 2 September 2016 /Accepted: 25 January 2017 # Springer-Verlag London 2017 Abstract 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 spe- cial 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 cut- ting cause lower wear distribution along the circumference of cutting tool. As a consequence to that, a significant re- duction 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. Keywords Rotary turning . Ultrasonic . Vibration . Wear . Surface roughness . Force 1 Introduction In conventional machining process, chip formation is commonly accompanied by heat generation in the cutting zone; thereby, tool wear acceleration occurred. This negatively affects surface quality and cutting forces [1, 2]. Thus, applying non-conventional methods have in- creasingly been attracting researchers to improve this con- dition. Rotary turning (RT) is one of these methods where rotary motion of cutting tool is added to typical motions existed in conventional turning (CT). Accordingly, a round insert type is used in which it rotates around its own axis [3, 4]. This additional movement is carried out in two types. The first one is self-propelled rotary turning. In this strategy, the cutting insert rotates by the reaction forces. In the second type, it rotates by using an external power source which is named actively driven rotary turn- ing [5]. In accordance with the fact that rotational movement of cutting tool could change the contact condition of tool and workpiece, various studies have been represented by researchers around this matter. Armarego et al. [ 6] modeled rotary turning and claimed that there are simi- larities in the mechanics and kinematics of RT and con- ventional oblique cutting, whereas differences are existed in the friction conditions. Suzuki et al. [7] developed a predictive force model for self-propelled rotary turning. It was stated that a sufficient inclination is needed so that the cutting tool can rotate. More than 60 times increment in tool life during driven rotary turning compared to CT was reported by Lei and Liu [ 8]. In another work, Dessoly et al. [9] represented a thermal model to esti- mate heat distribution on the tool faces in RT and CT. It was shown that due to providing cooling cycle for the cutting edge in RT, 50 °C reduction in temperature was achieved compared to non-rotating tool. Kishawy et al. [10] investigated flank wear propagation during RT of hardened AISI 4340 steel. At the end, they developed a model which was able to predict the rate of flank wear in this process. * Saeid Amini amini.s@kashanu.ac.ir 1 Department of Manufacturing, Faculty of Mechanical Engineering, University of Kashan, Kashan, Iran Int J Adv Manuf Technol DOI 10.1007/s00170-017-0108-5