Effect on strength of ternary alloying additions in L1 sub 2 intermetallics

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1991

OSTI ID:5466368

Wu, Yuanpang

The thermodynamic properties of {l brace}111{r brace} antiphase boundaries (APBs) as well as the site preference of ternary additions in an A{sub 3}B intermetallic with L1{sub 2} structure are studied, using a thermodynamic model. A survey of the results from a variety of ternary alloying additions to Ni{sub 3}Al has shown that there is a conflict in the actual role which solid solution strengthening plays in the athermal increment of yield strength. For instance, a good quantitative agreement with linear concentration law is observed only in alloys with stoichiometric compositions but not in the general case of non-stoichiometric alloys. In the light of the possibility that micro-segregation could explain the experimental discrepancy, the author extends the binary solid solution strengthening theory to the ternary system in an L1{sub 2} structure for the four real systems of Ni-Al-Si, Ni-Al-Ti, Ni-Al-Hf, and Ni-Al-V. It is found that ternary site preference plays an important role in the ternary solid solution strengthening theory with L1{sub 2} structure. Good quantitative agreement was found between the calculated and experimentally measured strength for both stoichiometric and nonstoichiometric alloys.

• Research Organization: Columbia Univ., New York, NY (United States)
• OSTI ID: 5466368
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOY SYSTEMS
ALLOYS
ALUMINIUM ALLOYS
ELEMENTS
HAFNIUM
HAFNIUM ALLOYS
INTERMETALLIC COMPOUNDS
MECHANICAL PROPERTIES
METALLURGICAL EFFECTS
METALS
NICKEL ALLOYS
SEMIMETALS
SILICON
SILICON ALLOYS
TERNARY ALLOY SYSTEMS
TITANIUM
TITANIUM ALLOYS
TRANSITION ELEMENTS
VANADIUM
VANADIUM ALLOYS
YIELD STRENGTH