Quality Assessment of Weldable Steel Mark P355NH from Decompression Chamber Construction for Diving

• Published in: Applied Mechanics and Materials Vol. 217-219; pp. 2381 - 2387
• Main Authors: Daşcău, Horia, Roşu, Radu Alexandru, Duma, Iuliana, Pascu, Romulus
• Format: Journal Article
• Language: English
• Published: Zurich Trans Tech Publications Ltd 12.11.2012
• Subjects: Hardness; Mechanical Property; Pressure Vessels
• ISBN: 3037855029; 9783037855027
• ISSN: 1660-9336; 1662-7482; 1662-7482
• DOI: 10.4028/www.scientific.net/AMM.217-219.2381

Non-alloyed P355NH steel according to EN 10028-3:2003 belongs to a group of fine-grained steels for pressure vessels being used in welded construction at decompression chamber for divers. Values of the chemical, structural and mechanical characteristics and steel toughness experimentally determined fit the analyzed steel in P355NH steel group according to EN 10028-3:2003. The toughness of the analyzed steel at the test temperature of -30°C is characterized by high values of fracture energy KV in longitudinal direction between 48 and 86 J and on transverse direction between 17 and 34J. Steel toughness at the test temperature of -30°C required by ABS standard (in Section 4/5.3 and Table 1) provides for breaking energy KV of min. 35J, with ductile fracture surfaces, value that is not respected at some lots of the three batches (A, B, C) of steel. Finally, based on the direct correlation established between HV10 hardness of the fine structure and the toughness it was made a selection of the lots of non-alloy steel P355NH which correspond to ABS norm for welded construction of the decompression chamber for divers