پديدآورندگان :
Najafizadeh N. M.Sc. student, Sustainable Manufacturing Systems Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Tehran, 16846-13114, Iran , Rajabi M. majid_rajabi@iust.ac.ir Assistant Professor, Sustainable Manufacturing Systems Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Tehran, 16846-13114, Iran; , Hashemi R. Assistant Professor, School of Mechanical Engineering, Iran University of Science and Technology,Tehran, 16846-13114, Iran , Amini S. Department of Manufacturing, Faculty of Mechanical Engineering, Kashan University, Kashan, 87317-53153, Iran
كليدواژه :
Ultrasonic Vibration , Hardness , Necking , Deformation Behavior , Grain Size.
چكيده فارسي :
Ultrasonic energy is a method used for applying severe plastic deformation on metal surfaces. The objective of this study is to investigate the effect of ultrasonic vibration on the hardness of St14 steel sheet. In the present work, a hemispherical-head tool, controlled by a CNC milling machine, shaped the sheet metal till the necking starts to happen. Conventional as well as the new ultrasonic test have been performed on a St14 steel sheet and obtained data were used to compare the hardness of the sheets. It is observed that the hardness of the sample shaped by applying ultrasonic vibrations to the tool with an amplitude of 15μm at 20 kHz increased significantly when compared to the sample shaped without using ultrasonic vibration, revealing the efficiency of the ultrasonic operation in increasing the hardness.