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Title: Using kinetics to avoid sigma phase formation on hyper duplex stainless weld cladding
The Hyper Duplex Stainless Steel HDSS enhanced corrosion resistance and toughness relies upon high alloying to obtain a balanced ferrite and austenite volume and pitting resistance equivalent number PREn. However, during welding, sigma phase precipitates might form, hindering corrosion and mechanical performance. Therefore, a kinetics model is developed to avoid the sigma phase's formation during welding and validated using physical simulation, finite element analysis (FEA), welding, and SEM characterisation. The sigma phase kinetics model produced calculated and validated temperature-time-transformation (TTT) and continuous-cooling-transformation (CCT) curves from which a 4°C/s cooling rate was found as a cooling rate threshold for sigma phase formation in this new material. Three-layered gas tungsten arc welding GTAW cladded mockup with 53 beads produced 24°C/s minimum cooling rate. Moreover, microscopy, mechanical, and corrosion testing attested it as a sigma-free weld.  more » « less
Award ID(s):
2052747 1822144 1539992
PAR ID:
10506690
Author(s) / Creator(s):
; ;
Publisher / Repository:
Taylor & Francis
Date Published:
Journal Name:
Science and Technology of Welding and Joining
Volume:
28
Issue:
9
ISSN:
1362-1718
Page Range / eLocation ID:
885 to 893
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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