Estimating the Parameters of Deformation Action by Ultrasonic Surface Hardening of Metals

Abstract

Electro-physical characteristics of MIS structures with HgTe-based single quantum wells S Dzyadukh, S Nesmelov, A Voitsekhovskii et al. Abstract. Developing the effective technologies of detail machining greatly depends on understanding the processes laid down in their basis. The technological methods based on electro-physical processes are considered to be attractive. These are the methods of surface plastic deforming which use the energy of ultrasonic oscillations. The peculiarities of these methods are characterized by high intensity and impulse character of the ultrasonic action. The paper presents the results of mathematical modeling of deformation processes under the impact of the ultrasonic tool on the surface layer of metals and alloys. The theoretical approach to studying the process of ultrasonic deforming allowed us to determine the mode parameters of impact and their quantitative correlations with the main characteristics of the deformation process. IntroductionUltrasonic plastic deforming as a separate technological method of the hardening and finishing operations is a modification of surface hardening, i.e. diamond smoothening, which is widely used in practice. The presence of ultrasonic oscillations during diamond smoothening leads to intensifying the plastic deformation of the surface layer of the material. It gives the possibility to provide machining at smaller values of static load, which considerably increases the technological perspectives of using such a method [1][2][3][4][5][6][7]. To extend further the sphere of using ultrasonic plastic deforming of different materials, from non-ferrous metals and alloys to hardened steels and details with coatings, it is required to determine the range of the mode parameters of the process mentioned. It will allow us to control both hardening and finishing effects in machining. Theory The process of ultrasonic plastic deforming should be considered in the following way: the movement of the deformer as a component of the oscillation system after its contact with the machined surface is the excitation of free oscillations [8]. Oscillations are of a harmonic sinusoidal character, which is confirmed by the results of high-speed photography of the process [9]. The movement of the deformer after its contact with the machined surface can be described as follows:

Revealing the technological modes range for ultrasonic surface hardening of cast iron

“…To describe the motion of the deformer the equation of free oscillations of the rod (1) in the model of ultrasonic plastic deformation the, was used [11]:…”

“…A generalizing characteristic of the hardening and finishing effect can be considered by the diameter of a single imprint (dotp) made by the impact of an ultrasonic instrument. In [11][12], a relation between the value (dotp) and the processing parameters is established:…”

“…The value of ϕ1 is determined by solving the equation (5) taking into consideration the known static force. The time moments t1 and t2 are determined by solving of the equations (6) and (7), respectively [11].…”

“…During studies the interrelationships of the regime parameters with changes in the microgeometry of the processed surface as well as the mechanical properties of the surface layer were revealed. The investigations were based on the known model of ultrasonic plastic deformation described in [11][12].…”