Process for stabilizing dimensions of duplex stainless steels for service at elevated temperatures

Patent · Thu Jan 01 00:00:00 EST 1981

OSTI ID:863861

Hull, Frederick C.; Tobin, John C.

Duplex stainless steel materials containing austenite plus delta ferrite, are dimensionally stabilized by heating the material to a reaction temperature between about 1050.degree.-1450.degree. F. (566.degree.-788.degree. C.), holding it at this temperature during transformation of delta ferrite to austenite plus sigma phase, and subsequently heating to a reversion temperature between about 1625.degree.-1750.degree. F. (885.degree.-954.degree. C.), whereby the sigma phase transforms back to ferrite, but the austenite remains dispersed in the ferrite phase. Final controlled cooling permits transformation of ferrite to austenite plus sigma and, later, precipitation of carbides.

• Research Organization: Hanford Engineering Development Lab., Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: EY-76-C-14-2170
• Assignee: The United States of America as represented by the United States Department of Energy (Washington, DC)
• Patent Number(s): 4,263,063
• Application Number: 06/055210
• OSTI ID: 863861
• Resource Relation: Patent File Date: 1979 Jul 05
• Country of Publication: United States
• Language: English

Related Subjects

process
stabilizing
dimensions
duplex
stainless
steels
service
elevated
temperatures
steel
materials
containing
austenite
plus
delta
ferrite
dimensionally
stabilized
heating
material
reaction
temperature
1050
degree
-1450
566
-788
holding
transformation
sigma
phase
subsequently
reversion
1625
-1750
885
-954
whereby
transforms
remains
dispersed
final
controlled
cooling
permits
precipitation
carbides
delta ferrite
materials containing
stainless steels
elevated temperatures
elevated temperature
stainless steel
reaction temperature
subsequently heating
steel material
controlled cooling
duplex stainless
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