The influence of shot peening and artificially ageing aluminium alloy 7075 on corrosion behaviour

Žagar, Sebastjan (author), Mrvar, Primož (author), Grum, Janez (author), Šturm, Roman (author)

This paper investigates the corrosion of shot peened AA7075 aluminium alloys aged at different temperatures. The surface integrity of the hardened layer was evaluated with SEM, EDS, differential scanning calorimetry, hardness, and roughness measurements, and in the end also with corrosion resistance tests. The research results indicated that there were significant differences in precipitates distribution between aluminium alloys artificially aged at different temperatures. As the ageing temperature increases, the microhardness decreases, which influences the final roughness condition of the surface layer after shot peening. The results of potentiodynamic polarisation tests indicate that shot peening enables shifting the pitting potential to positive values, which ensures slightly higher corrosion resistance. SEM images confirmed the dissolution of the aluminium matrix near the separated iron-rich phases of the Al$_x$ form (Fe, Mn) by the action of galvanic cells.

• Language: English
• Keywords: aluminium alloy 7075, shot peening, ageing temperature, pitting corrosion, cyclic polarisation, intermetallic particles
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering; NTF - Faculty of Natural Sciences and Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: 13 str.
• Numbering: Vol. 15, iss. 9, art. 3094
• PID: 20.500.12556/RUL-136334
• UDC: 620.1:621.787.6:669.715
• ISSN on article: 1996-1944
• DOI: 10.3390/ma15093094
• COBISS.SI-ID: 105816579
• Publication date in RUL: 25.04.2022

Record is a part of a journal

• Title: Materials
• Shortened title: Materials
• Publisher: MDPI
• ISSN: 1996-1944
• COBISS.SI-ID: 33588485

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: aluminijeva zlitina 7075, udarno utrjevanje, temperatura staranja, jamičasta korozija, ciklična polarizacija

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0270
• Name: Proizvodni sistemi, laserske tehnologije in spajanje materialov