Niobium or tantalum based high specific strength inter metallic compounds and alloys

• US 5,486,242 A
• Filed: 05/15/1995
• Issued: 01/23/1996
• Est. Priority Date: 11/26/1990
• Status: Expired due to Fees

• Current Assignee: Office National D'Etudes et de Recherches Aerospatiales
• Original Assignee: Office National D'Etudes et de Recherches Aerospatiales
• Inventors: Delaunay, Christophe, Naka, Shigehisa, Khan, Tasadduq, Thevenin, Pierre, Marty, Michel, Walder, Andre
• Primary Examiner(s): Simmons, David A.
• Assistant Examiner(s): Koehler, Robert R.
• Application Number:
  US08/440,659
• Time in Patent Office: 253 Days
• Field of Search: 148/422, 148/442, 420/426, 420/427, 420/580, 420/588
• US Class Current: 148/422
• CPC Class Codes: C22C 27/02 Alloys based on vanadium, niobium, or tantalum
• CPC Class Codes: C22C 30/00 Alloys containing less than 50% by weight of each constituent

Abstract

Tantalum-based and niobium-based alloys made up entirely of a crystalline medium exhibiting a substantially continuous centered cubic structure, comprising an intermetallic compound of formula Ti₂ AlMo, and having the following compositions on an atomic basis:

______________________________________                                    

Ta + Cr 20 to 35% Cr 0 to 5% Ti 20 to 40% Al 8 to 20% Mo 8 to 20%, ______________________________________

wherein the concentration of Ta is less than 30%; and______________________________________ Nb + Cr 20 to 60% Cr 0 to 5% Ti 20 to 40% Al 8 to 20% Mo 8 to 20%.______________________________________ .

Claims

1. Niobium-based alloy made up entirely of a crystalline medium exhibiting a substantially continuous centered cubic structure, comprising an intermetallic compound of formula Ti₂ AlMo, and having a composition on an atomic basis in the following domain:

space="preserve" listing-type="tabular">______________________________________ Nb + Cr 20 to 40% Cr 0 to 5% Ti 30 to 40% Al 15 to 20% Mo 15 to 20%, ______________________________________

the ratio Ti;

Al;

Mo being approximately 2;

1;

1, and the concentration of Nb being not more than 37%.

2. Tantalum-based alloy made up entirely of a crystalline medium exhibiting a substantially continuous centered cubic structure, comprising Ta, Cr, Ti, Al and Mo, wherein the concentrations of Ta and Cr on an atomic basis are:

space="preserve" listing-type="tabular">______________________________________ Ta 15 to less than 30%, Cr 0 to 5%, ______________________________________

the balance consisting essentially of Ti, Al and Mo in an atomic ratio Ti;

Al;

Mo of approximately 2;

1;

1, wherein Ti, Al and Mo are present in the alloy in the form of an intermetallic compound of formula Ti₂ Al Mo in an amount which does not exceed 80% of the alloy on an atomic basis.

3. Niobium-based alloy made up entirely of a crystalline medium exhibiting a substantially continuous centered cubic structure, comprising an intermetallic compound of formula Ti₂ AlMo, and having the composition:

space="preserve" listing-type="tabular">______________________________________ Nb 37% Ti 30% Al 15% Mo 15% Cr 3%, ______________________________________

and being in the form of a single phase which has a crystallographic structure of type B2 at ambient temperature.

4. Niobium-based alloy made up entirely of a crystalline medium exhibiting a substantially continuous centered cubic structure, comprising an intermetallic compound of formula Ti₂ AlMo, and having the composition:

space="preserve" listing-type="tabular">______________________________________ Nb 30% Ti 34% Al 17% Mo 17% Cr 2%, ______________________________________

and being in the form of a single phase which has a crystallographic structure of type B2 at ambient temperature.