Mechanical characterisation of a P91 weldment by means of small punch fracture testing

• Published in: The International journal of pressure vessels and piping Vol. 105-106; pp. 28 - 35
• Main Authors: Gülçimen, B., Durmuş, A., Ülkü, S., Hurst, R.C., Turba, K., Hähner, P.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2013
• Subjects: Base metal; Charpy test; Ductile brittle transition; Ductile to brittle transition temperature; Ferritic stainless steels; Fracture; Fracture mechanics; Heat resistant steels; Notch tests; P91 steel; Punches; Small punch testing technique; Transition temperature; Weld metal; Weldments; Charpy test; Ductile to brittle transition temperature; Fracture; Small punch testing technique; P91 steel
• ISSN: 0308-0161; 1879-3541
• DOI: 10.1016/j.ijpvp.2013.02.005

Small Punch fracture tests were carried out in order to determine low temperature mechanical behaviour of a P91 steel weldment: weld metal, base metal, Heat Affected Zone-Fine Grained and Heat Affected Zone-Coarse Grained. The Heat Affected Zone-Fine Grained showed superior tensile properties in terms of displacement at fracture (ductility) and strength (maximum force) compared to the other zones, which became more pronounced at lower temperatures, whilst the weld metal exhibited inferior behaviour. Ductile Brittle Transition Temperatures were evaluated from Small Punch results for all zones and the results of base metal and weld metal were correlated with the transition temperatures obtained from Charpy V notch tests according to the CEN Code of Practice for Small Punch testing. Heat Affected Zone-Fine Grained with its finest structure exhibited the lowest transition temperature and the weld metal the highest. Heat Affected Zone-Coarse Grained and base metal were found to have quite similar transition temperature values. ► Fracture properties of a P91 steel weldment are determined by Small Punch tests. ► HAZ-FG exhibits superior mechanical properties compared to the other zones. ► Correlation factors between the Charpy and SP transition temperatures are calculated.