A Review of Haynes® 230® and 617 Alloys for High Temperature Gas Cooled Reactors

Michael Katcher; Dwaine L. Klarstrom

doi:10.4028/www.scientific.net/MSF.595-598.511

Paper Titles

Corrosion of T91 Steel in LBE: Contribution to the Study of the Pb–Bi–O–Fe–Hg System - Thermodynamic Description of PbO–Fe₂O₃
p.473

Electrochemical Study of the Corrosion of Metals in Molten Fluorides
p.483

Influence of Al on the High Temperature Corrosion Behaviour of Inconel 617 in VHTR Primary Coolant Atmosphere
p.491

Oxide Layers Mechanical Properties for Ni Base Alloys in HTR Environment
p.501

A Review of Haynes^® 230^®and 617 Alloys for High Temperature Gas Cooled Reactors
p.511

High Temperature Oxidation of Fe-9Cr-1Mo Steel in Liquid Metal
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Corrosion Mechanisms of Ni-Base Alloys in Pressurized Water Reactor Primary Conditions
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Characterization of the Oxide Films Formed at the Surface of Ni-Base Alloys in Pressurized Water Reactors Primary Coolant by Transmission Electron Microscopy
p.539

Overview of Coating and Compatibility Research for Fusion Energy in the U.S.
p.549

HomeMaterials Science ForumMaterials Science Forum Vols. 595-598A Review of Haynes® 230® and 617 Alloys for High...

A Review of Haynes^® 230^®and 617 Alloys for High Temperature Gas Cooled Reactors

Abstract:

HAYNES® 230® and 617 alloys are competing for use on Generation IV, high temperature gas cooled reactor components because of good high temperature creep strength in the temperature range between 760°C and 982°C and resistance to oxidation in the gas cooled reactor environment. A review of the metallurgy affecting the properties in each alloy will be discussed. Grain size and carbide precipitation developed during fabrication effect short term and long term ductility, fatigue, and creep. For example, 230 alloy has a finer grained structure which promotes fatigue strength with a slight sacrifice in creep strength. The 617 alloy has a coarser grain structure which provides slightly higher creep resistance while sacrificing some fatigue strength. Thermal aging also introduces gamma prime precipitation to the 617 alloy as well as grain boundary carbides, and this, in addition to grain boundary oxidation, reduces the low cycle fatigue strength of 617 alloy compared to 230 alloy. Independent studies have shown that 230 alloy possesses higher resistance to thermal fatigue than 617 alloy. However, welds of both base metals with similar weld composition have about the same thermal fatigue life. Cooling rates from solution annealing temperatures during processing effect the ductility and creep strength of these alloys with the highest cooling rates preferred for retention of ductility and creep strength. The reason; slow cooling rates promote carbide precipitation in the grain boundaries which reduces ductility and creep strength.