Microstructural mechanical and corrosion properties of SS304/HEA surface layer produced by Friction Stir Processing

• Published in: Journal of alloys and compounds Vol. 953; p. 170153
• Main Authors: Krishna, S. Aravind, Radhika, N., Saleh, Bassiouny, Manivannan, S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25-08-2023
• Subjects: Friction Stir Processing; Grain refinement; High entropy alloys; Recrystallisation; Surface modifications; Friction Stir Processing; High entropy alloys; Recrystallisation; Surface modifications; Grain refinement
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2023.170153

Stainless steel SS304 is employed in great many domestic and industrial applications. The material's ability to tolerate extremely corrosive environments is hampered by harsh condition applications, and the mechanical qualities are also reduced that demanding the need for surface modification techniques to alter the surface at the microstructural level. In this study, CoCrFeCuTi High Entropy Alloys (HEA) powder was reinforced on an SS304 steel substrate employing a Friction Stir Processing (FSP) approach to achieving a high degree of grain size refinement and which leads to improving mechanical properties. The microstructural characterisation of the milled powder and the processed specimen followed by mechanical and corrosive properties are analysed. The morphology of the milled powder was irregular fragments and 17 µm as the mean particle size with the presence of BCC phase. The microstructural analysis of the processed substrate with HEA exhibited better grain refinement and neat dispersion of HEA reinforcement. The Vickers microhardness and tensile strength of the FSP-processed substrate with HEA were improved when compared with the FSP-processed substrate with no HEA. The electrochemical corrosion analysis affirms that the FSP-processed substrate with HEA is better resistant to corrosion.
•CoCrFeCuTi HEA synthesised by ball milling exhibited irregular fragmented particles of mean size 17 µm and BCC phase.•The FSP sample with HEA offered fine grain refinement with an average grain size 1.8 µm promoting the property enhancement.•The microhardness and tensile strength of HEA reinforced steel is improved against the processed base metal.•The corrosion test outcome showed better corrosion resistance for HEA reinforced steel aided by the fine grain refinement.