Microstructure/mechanical property relationship in a DS cast Ni[sub 3]Al-base alloy

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Journal of Materials Engineering and Performance; (United States)

DOI:https://doi.org/10.1007/BF02661745· OSTI ID:5363004

Han, Y F; Wang, Y M ^[1]; Chaturvedi, M C ^[2]

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1. Inst. of Aeronautical Materials, Beijing (China)
2. Univ. of Manitoba, Winnipeg, Manitoba (Canada). Dept. of Mechanical and Industrial Engineering

A Ni-Al-Mo directionally solidified (DS) casting [gamma][prime]-base superalloy, with the chemical composition (wt%) 7.5 to 8.5% Ni, 10 to 14% Al, Mo [<=] 0.15% B, has been developed for advanced gas turbine blades and vanes. The mechanical properties of this alloy have been determined by tensile tests at room temperature and in the temperature range 700 to 1,000 C and by stress-rupture tests in the temperature range 760 to 1,100 C. The microstructures of the as-cast and homogenized specimens and of specimen after creep deformation at 1,000 to 1,100 C have been examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and optical microscopy techniques. The results show that this alloy has a high yield strength from room temperature up to 1,100 C, excellent creep resistance at temperatures up to 1,100 C, as well as a lower density and higher melting point than currently available nickel superalloys. The microstructural observations and analysis indicate that the superior mechanical properties of this alloy may be attributed to solid solution hardening by the large molybdenum addition, second-phase strengthening by [gamma] phase and other minor phases that precipitate in various temperature ranges, the formation of a [gamma] raft structure during creep, and to the existence of high-density misfit dislocation networks at [gamma][prime]/[gamma] interface areas due to a high value of [gamma][prime]/[gamma] misfit.

• OSTI ID: 5363004
• Journal Information: Journal of Materials Engineering and Performance; (United States), Journal Name: Journal of Materials Engineering and Performance; (United States) Vol. 2:4; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals &amp; Alloys-- Structure &amp; Phase Studies
360103 -- Metals &amp; Alloys-- Mechanical Properties
ALLOYS
ALUMINIUM ALLOYS
BORON ADDITIONS
BORON ALLOYS
DATA
ENGINES
EXPERIMENTAL DATA
GAS TURBINE ENGINES
HEAT ENGINES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
INFORMATION
INTERNAL COMBUSTION ENGINES
MATERIALS
MECHANICAL PROPERTIES
MICROSTRUCTURE
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NICKEL BASE ALLOYS
NUMERICAL DATA