Influence of metallic oxide nanoparticles on the mechanical properties of an A-TIG welded 304L austenitic stainless steel

Baloš, Sebastian (author), Dramićanin, Miroslav D. (author), Janjatovic, Petar (author), Kulundzic, Nenad (author), Zabunov, Ivan (author), Pilić, Branka (author), Klobčar, Damjan (author)

Austenitic stainless steels represent a significant aerospace material, being used for various castings, structural components, landing gear components, afterburners, exhaust components, engine parts, and fuel tanks. The most common joining process is tungsten inert gas (TIG) welding, which possesses many advantages such as suitability to weld a wide range of ferrous and non-ferrous metals and alloys, providing high quality welds with good mechanical properties. Its major disadvantage is low productivity due to low penetration and welding speed. This can be overcome by introducing an activating flux before welding. The activating flux reverses the material flow of the weld pool, significantly increasing penetration. Therefore, shielding gas consumption is reduced and welding without a consumable is enabled. However, the consumable in conventional TIG also enables the conditioning of the mechanical properties of welds. In this study, Si and Ti metallic oxide nanoparticles were used to increase the weld penetration depth, while bend testing, tensile, and impact toughness were determined to evaluate the mechanical properties of welds. Furthermore, optical emission spectroscopy, light, and scanning electron microscope were used to determine the chemical compositions and microstructures of the welds. Chemical compositions and weld mechanical properties were similar in all specimens. The highest tensile and impact properties were obtained with the specimen welded with the flux containing 20% TiO$_2$ and 80% SiO$_2$ nanoparticles. Although lower than those of the base metal, they were well within the nominal base metal mechanical properties.

• Language: English
• Keywords: oxide flux, activated tungsten inert gas welding, mechanical properties, 304L stainless steel
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 11 str.
• Numbering: Vol. 13, iss. 20, art. 4513
• PID: 20.500.12556/RUL-134486
• UDC: 621.791.75:669.14.018.8(045)
• ISSN on article: 1996-1944
• DOI: 10.3390/ma13204513
• COBISS.SI-ID: 44227843
• Publication date in RUL: 18.01.2022

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.
• Licensing start date: 12.10.2020

Secondary language

• Language: Slovenian
• Keywords: oksidni delci, aktivirano varjenje TIG, mehanske lastnosti, nerjavno jeklo 304 L