Effects of B and Zr on the creep and fatigue crack growth behavior of a Ni-base superalloy

Journal Article · Sun May 01 04:00:00 EDT 1983 · Metall. Trans., A; (United States)

DOI:https://doi.org/10.1007/BF02644294· OSTI ID:6364305

Floreen, S; Davidson, J M

The effects of 0.006 wt pct B and/or 0.05 wt pct Zr on the 650 C creep and fatigue properties of a nickel-base superalloy were evaluated. Additions of B and Zr markedly improved the smooth specimen creep properties and the threshold stress intensity values for creep crack growth. The additions had no effect on the crack growth rates in creep or fatigue. No changes in microstructure, fracture appearance, or grain boundary sliding behavior due to B and Zr could be seen. The benefits of B and Zr were much greater in tests in air than in helium, and the primary effect of these additions was to minimize the harmful effects of oxygen. The general results can be explained by postulating that B and Zr minimize the deleterious change in interfacial energy caused by oxygen, but a clearer understanding of the nature of creep threshold values is needed.

• Research Organization: Inco Alloy Products Research Center, Suffern, NY
• OSTI ID: 6364305
• Journal Information: Metall. Trans., A; (United States), Journal Name: Metall. Trans., A; (United States) Vol. 14A; ISSN MTTAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
BORON
CHEMICAL REACTIONS
CORROSION
CRACK PROPAGATION
CREEP
CRYSTAL STRUCTURE
ELEMENTS
FLUIDS
GASES
GRAIN BOUNDARIES
HELIUM
INTERGRANULAR CORROSION
MECHANICAL PROPERTIES
METALLURGICAL EFFECTS
METALS
MICROSTRUCTURE
NICKEL ALLOYS
NICKEL BASE ALLOYS
NONMETALS
RARE GASES
SEMIMETALS
STRESS INTENSITY FACTORS
TRANSITION ELEMENTS
ZIRCONIUM