Deep Hardening of Inner Cylindrical Surface by Periodic Deep Rolling - Burnishing Process

Abstract

Severe surface plastic deformation is one of the methods to improve the mechanical behavior of metallic components, because such a treatment generates a hardened near-surface layer with compressive residual stresses. As is well known, deep rolling (DR) stands out against a background of the others mechanical techniques owing to maximum values of hardness, residual stress and hardening depth attained. In this work, an accomplished version of DR is proposed, which may be regarded as a superposition of DR and burnishing (B) processes in order to elevate those characteristics up to larger values. In contrast to consecutive application of DR and B techniques, the new approach allows to alter them multiply within one and only technological process with no increasing the working duration and without the need of any additional equipment. The working principles of the device are described. The dependences "depth-hardness" are presented. Numerical assessment of the residual stress is performed. The micro-photographies demonstrate an increase in the structural homogeneity of the near-surface layer material. The results indicate that the newly developed technique attains its main goals.

Deep Rolling Techniques: A Comprehensive Review of Process Parameters and Impacts on the Material Properties of Commercial Steels

“…Furthermore, studies on deep rolling coupled with heat treatment and/or elevated temperature [73][74][75][76], cryogenic treatment [39,77], aging [56], and certain surface treatments like shot peening [78,79], burnishing [80], and ultrasonic-induced hammering [81][82][83][84] were testified in the recent past. The major objective was to complement DR with the advantages of the latter.…”

“…The FEA methodology developed was reported to be efficient for yielding faster simulation with higher accuracy of results. Some application-specific studies involving the simulation of DR of crankshafts [114,147,148], railway axels [109,149], cylinder inner surfaces [80,150], fine blanking punch edges [22], turbine/compressor blades [105,134], torsion bars [120], and welded joints [124,126,151] revealed the potential of numerical techniques for effective assessment and optimization of process parameters. However, the material models and boundary conditions along with process kinematics were reported to be the key factors that must be modeled appropriately to obtain a reliable conclusion.…”

Assessment of the Depth of the Deformed Layer in the Roller Burnishing Process

“…Precise determination of the depth of the plastically deformed layer is difficult due to slight deformation at the boundary of the plastic and elastic zone, the lack of visible changes in the microstructure, and minimal changes in microhardness. Most studies determine the depth of the plastically deformed layer by measuring microhardness in the cross section of the sample [24,25]. Figure 3 shows the scheme of the original measurement method that consists in determining the thickness of the deformed layer using rings.…”

An axisymmetric nodal averaged finite element

“…A surface hardening process of a steel rod by means of deep rolling (DR) is studied. DR is an extremely complex process (see for example Radchenko et al (2015) and Gryadunov et al (2015)) because of high gradient values of tensor fields and due to the induced non-uniformity of a material. As a rule, such problems are solved in a threedimensional statement (despite a workpiece looks like an axisymmetric body) when a small representative part of a detail is considered together with some reasonable boundary conditions.…”