The Effect of Shot Peening on Additively Manufactured 316L Stainless Steel for the Marine Transportation Industry

Author:  L. Bonnici1, J. Buhagiar1, G. Cassar1, K. A. Vella1, J. Chen2, X.Y. Zhang2, M.Y. Liu2, Z.Q. Huang2, A. Zammit1 1 Department of Metallurgy and Materials Engineering, University of Malta, Msida, Malta 2 School of Materials Science and Engineering, Southeast
Source:  ICSP14 Milan
Doc ID:  2022077
Year of Publication:  2022
Abstract:  
Abstract In the marine transportation industry, the harsh environment during voyage leads to severe corrosion failure or mechanical breakdowns. Hence, continuous and preventive maintenance is required. Additive manufacturing (AM) can potentially be used to reduce the downtime associated with replacement of components by printing the required parts directly from the design itself. In this study, shot peening (SP) was applied as a posterior treatment on AMed 316L stainless steel (SS) with the aim to increase the mechanical properties at the surface and the surface characteristics without creating a detriment to the alloy’s corrosion resistance. A 44% increase in surface hardness from 231 ± 38 HV0.2 to 334 ± 61 HV0.2 was measured after SP, while the affected depth was of around 200 μm. SP also resulted in Ra values of 10 ± 1 μm for as-printed samples, which was reduced to 5 ± 1 μm after SP. Additionally, the SP treatment induced a surface compressive residual stress of 589 MPa. Corrosion results were not favourable for the SP-ed samples. However, the overall results suggest that the use of AM SP parts may indeed be a suitable contender for use in selected maritime components. Keywords Additive manufacturing, shot peening, residual stress measurement, corrosion resistance