The formation of a quasi-periodic surface profile by means of dislocation slip

Abstract

Abstract. This work presents the experimental results concerning the research of the morphology of the face-centered cubic (FCC) single crystals surface after compression deformation. Our aim is to identify the method of forming a quasiperiodic profile of single crystals with different crystal geometrical orientation. A set of modern methods as optical and confocal microscopy is applied. It is done to determine the morphology of surface parameters. The results show that the octahedral slip is an integral part of the formation of quasiperiodic profile surface and is starting with the initial strain. We present values of shear quantity directly in shear traces, meso-and macrobands and in shear tracks shift within them. The similarity of the process of surface profile forming at different levels of scale is given. Finally, we suppose that octahedral slip is the main way to form quasiperiodic deformation relief. We compare our results to published data and identify common regularities for various metal FCC single crystals with different deformation methods. The experimental results presented can be used for mathematical modeling of plastic deformation. IntroductionChanges in topology of solid surface after deformation are of interest to researchers from various branches of science for many years. The experimental data and results of mathematical models indicate that folding, wrinkling, extrusion and intrusion, checkerboard distribution regions, etc. are frequent and appear in a variety of load conditions. This process is typical for the poly-and single crystals, the folds can be observed in geology and metal forming. Folding being manifested in different ways of deformation, it has various manifestations and can be initiated as a slip and twinning.The results of finite element modeling of the emergence of roughness during plastic deformation of polycrystalline aluminum are given in article [1]. Results showed that texture samples and the direction of strain influence the formation of roughness. There are "ribbed ridging profiles" and the surface of the "orange peel shape". The paper also indicates that the Taylor factor affects the type of roughness. Article [2] represents the experimental data which show that the size and orientation of the grain influence roughness during plastic deformation. The results were obtained by the example of polycrystalline aluminum alloys. In all cases, there is a quasi-periodic surface profile after the deformation.The series of works by Gubernatorov V.V. with colleagues had called the reason for corrugating surface distortion of the material layers. They also show that the corrugation may be formed in a structurally homogeneous material (single crystal), that is, availability of basic stress concentrators is