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The effect of slide burnishing (SB) on the high‐cycle fatigue (HCF) performance of 2024‐T3 high‐strength aluminium alloy has been studied. After SB with optimum basic process parameters under ‘minimum roughness’ criterion, the 107 cycle fatigue strength increases with 25% – from 180 to 225 MPa, fatigue life is increased more than 50 times, and the roughness obtained reaches up to Ra = 0.05 μm. Further, various combinations of burnishing force and deforming element radius have been applied to reach maximum HCF performance despite roughness obtained. It has been established that with the optimum combination under ‘maximum HCF performance’ criterion, 107 cycle fatigue strength increases with 44% – from 180 to  260 MPa as the roughness obtained is Ra = 0.25 μm. This significant enhancement in the HCF performance is due to introduced beneficial residual compressive stresses. They shift the fatigue crack initiation site from surface to subsurface layers and, as a result, the nucleation and propagation of the first‐mode fatigue cracks are retarded. In order to establish the fatigue limit (based on 2  ×  108 cycles), a combined approach, based on limited Wöhler's curve and Locati's method, has been applied. The fatigue limit of 2024‐T3 high‐strength aluminium alloy can be increased up to 250 MPa using SB with optimal basic parameters under ‘maximum HCF performance’ criterion.

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Chromium-nickel steels are widely used in various fields of the engineering practice because of their increased corrosion resistance. One of the most used chromium-nickel steel is AISI 316Ti. It is known from the engineering practice that processing this steel by cutting creates difficulties and problems. However, there is no information regarding the effectiveness of the slide burnishing (SB) method in terms of quality of the processed surface of this chromium-nickel steel. A comprehensive experimental and FEM study of the surface integrity of slide burnished specimens made of AISI 316Ti austenitic stainless steel has been carried out. The effect of the SB parameters on the obtained roughness, microhardness, residual stress, fatigue strength (life) and wear resistance has been studied. A fully coupled thermal-stress FEM analysis has been conducted to be appreciated the effect of the generated temperature in SB process on the residual stress formation. The SB of AISI 316Ti steel achieves: roughness of R a = 0.055 lm; micro-hardness increased by more than 32%; significant wear resistance; introduced residual stress with a maximum absolute value, which significantly exceeds the yield limit of the bulk material; increased fatigue strength by 38.9%; fatigue life increasing more than 385 times. The obtained experimental outcomes for the main characteristics of the surface integrity prove that SB can be successfully applied as a mixed burnishing for finishing symmetrical rotational components made of chromium-nickel steels.

A reliable finite element modelling (FEM) approach to the spherical motion burnishing (SMB) process is developed with a view to gaining a fundamental understanding of the process and its optimization. SMB is a patented method for mechanical surface treatment of external cylindrical faces aimed at the enhancement of the fatigue life of the metallic component as well as its roughness, micro-hardness, depth hardening, wear, and corrosion resistance. A special feature of SMB is its kinematics: the tool motion is a superposition of a spherical movement and a rectilinear translation with respect to the workpiece. In order to decrease the FEM problem size, an approximated kinematic theory for the SMB is developed. In accordance with this theory the tool motion is approximated with a series of planar movements. As a result, a plane strain SMB FEM model is developed. The initial roughness is modelled in order to to achieve a more realistic representation of the workpiece geometry. To establish the flow stress and sliding friction coefficient, a combined approach is developed which contains mechanical tests, sensitivity FEM analysis, and inverse FE analysis of the corresponding pushing process. A planned numerical experiment is carried out on the basis of the created SMB FEM model. Six regression models of the treated layer characteristics are obtained and analysed on the basis of the FEM simulations. The FEM results are evaluated and compared to the experimental ones and their validity is proved. Finally, the regression models are used as objective functions in a multi-objective optimization problem formulation of the SMB process. As a result, the optimal combination of the governing SMB parameters is established.

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