**J. Antonio Travieso-Rodriguez**

Dr. Travieso-Rodriguez works as Associate Professor at Mechanical Engineering department at Universitat Politecnica de Catalunya, from 2006. He received his PhD degree in Mechanical ` Engineering, fluids and Aeronautic, in 2010. His research lines are in the areas of Development and characterization of the Burnishing process in metals and Additive Manufacturing. He has published more than 60 research paper in indexed journals, 3 invention patents and 2 utility models. He has been Supervisor of 6 Doctoral theses as well.

**Stoyan Slavov 1,\*, Diyan Dimitrov 2, Mariya Konsulova-Bakalova <sup>1</sup> and Dimka Vasileva <sup>1</sup>**


**Abstract:** The present work describes an experimental investigation of the fatigue durability of AISI 304 and AISI 316L austenitic stainless steels, which have regular reliefs (RR) of the IV-th type, formed by ball burnishing (BB) on flat surfaces, using a computer numerical control (CNC) milling center. The methodology and the equipment used for obtaining regular reliefs, along with a vibration-induced fatigue test setup, are presented and described. The results from the BB process and the fatigue life experiments of the tested austenitic stainless steels are gathered, using the approach of factorial design experiments. It was found that the presence of RR of the IV-th type do not worsen the fatigue strength of the studied steels. The Pareto, *t*-test and Bayesian rule techniques are used to determine the main effects and the interactions of significance between ball burnishing regime parameters. A stochastic model is derived and is used to find when the probability of obtaining the maximum fatigue life of parts made of AISI 304 or 316L reaches its maximum value. It was found that when the deforming force, the amplitude of the sinewaves and their wavenumber are set at high values, and the feed rate is set at its low value, the probability to reach maximum fatigue life for the parts made of AISI 304 or 316L is equal to 97%.

**Keywords:** ball burnishing; regular reliefs; surface topography; austenitic stainless steel; fatigue life; *t*-test; Bayesian rule
