BEGIN:VCALENDAR
VERSION:2.0
METHOD:PUBLISH
BEGIN:VEVENT
ORGANIZER;CN=ESTAD 2023:mailto:info@metec-estad.com
LOCATION:Room 15a
SUMMARY:Comparison of mechanical properties of artificial and natural aged cold formed S700 rectangular hollow section
DESCRIPTION:Formed steel sections are widely used in construction applications due to their relatively high strength and stiffness properties. Especially, cold-formed welded hollow sections provide cost-efficient and environmentally friendly alternatives compared to hot-formed sections. Cold deformation causes work-hardening of the material, which resulting in enhanced strength, although a corresponding loss of elongation and toughness. The aim of this work is to compare mechanical properties of i) as produced, ii) artificial aged (250 °C for 1 h) and iii) naturally 5-years aged cold formed S700 rectangular hollow section. The investigated hot rolled steel strip was produced thermomechanical rolling followed by direct quenching. The dimension of the investigated hollow section was 120x120x10 mm and the corner radii and the other tolerances compliant with EN 10219. Tensile properties and Charpy-V impact toughness were determined for the flat and corner area of the hollow section. The results showed that the tensile strength in the corner was slightly higher in comparison with the flat side, revealing higher cold deformation rate in the corner. Artificial ageing increased the strength level relatively higher than cold forming without losing any elongation properties. The impact energies were at the high level at -40 °C and -60 °C in cold formed and aged materials. Even at -80 °C, the CV results were 118 J/cm2. It is also notable that no difference in CV values between the flat and the corner samples were observed. Thus, the results showed that the flat side specimens testing provides sufficient information of mechanical properties of the cold formed rectangular hollow sections and no need demanding corner sample testing when the structural hollow section is produced by using the thermomechanical controlled and direct-quenched base material. Furthermore, results showed that cold formed S700 is excellent for offshore steels, as steels are used even colder conditions as before. 
CLASS:PUBLIC
DTSTART:20230615T121000
DTEND:20230615T123000
END:VEVENT
END:VCALENDAR