Assessment of deposit microstructure and all-weld and joint creep performance of the matching filler metal for the MARBN alloys

ABSTRACT

Substantial effort has been made in validating the MARBN alloys aiming to introduce new materials for the next-generation power plants. One of the essential tasks was to develop a welding filler metal for the component construction. The weld and the joint needed to provide adequate properties matching the base materials. Through two collaborative projects, IMPEL and IMPULSE, a matching composition filler metal, Chromet 933, was designed and evaluated. This paper introduces the assessment carried out on microstructure of the weld metal. Short–medium duration creep tests were conducted on all-weld metal and welded joints made from forged plate and pipe with IBN-1 composition to evaluate the creep performance. The initial results were encouraging. The stress rupture properties of the MARBN IBN-1 all-weld deposit and welded joints were compared with those of P92 steel weld and joints. The advantages of the new alloy and filler metal are evident.

KEYWORDS:

• Cr-Mo creep-resisting alloys
• MARBN
• IBN-1
• Cr-Mo filler metal
• creep properties

Acknowledgments

The authors gratefully acknowledge the funding from Innovate UK, under Project IMPULSE: ’Advanced Industrial Manufacture of Next-Generation MARBN Steel for Cleaner Fossil Plant’, Innovate UK File Ref. 102468; and their project partners within IMPEL Project and IMPULSE Project: Doosan Babcock Ltd., Goodwin Steel Castings Ltd., Alstom Power (now GE Energy), Uniper Technologies Ltd., IMPACT PowerTech Ltd., Wyman-Gordon Ltd., Loughborough University, University of Nottingham, University of Birmingham, NUI Galway and University of Limerick.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Innovate UK [Innovate UK File Ref. 102468].