PERSPECTIVES AND PROBLEMS IN SHOT PEENING, A MECHANICAL TREATMENT TO IMPROVE THE FATIGUE BEHAVIOUR OF STRUCTURAL PARTS

Shot peening is a mechanical surface treatment used for improving the mechanical behaviour of metallic materials and structural parts. Its most frequent use is related to fatigued components, but it is effective also to delay or prevent fretting, stress corrosion cracking and hydrogen embrittlement. Its positive effect on the mechanical behaviour of components is related to the ability to induce compressive residual stresses in the sub-surface layer of materials and to work harden the surface. Notwithstanding the first applications of shot peening date back to many years ago, this treatment is not fully understood and still object of research, due to its great potentiality for further development in future applications. In this paper, the author describes his recent experiences and results in shot peening and underlines some research lines for the future developments of shot peening.