Methods and materials for attaching ceramic and refractory metal casting cores

• US 20070068649A1
• Filed: 09/28/2005
• Published: 03/29/2007
• Est. Priority Date: 09/28/2005
• Status: Abandoned Application

• Current Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Verner, Carl, Turkington, Michael, Bartholomew, Mark
• Application Number:
  US11/237,322
• Publication Number:
  US 20070068649A1
• Time in Patent Office: Days
• US Class Current: 164/519
• CPC Class Codes: B22C 9/04 Use of lost patterns
• CPC Class Codes: B22C 9/103 Multipart cores
• CPC Class Codes: B22C 9/12 Treating moulds or cores, e.g. drying, hardening

Abstract

A slurry is used to secure a metallic casting core to a ceramic casting core. The slurry may be introduced between the metallic and ceramic casting cores and hardened. The slurry may comprise zircon and aqueous colloidal silica.

Claims

1. A method for attaching a metallic casting core to a ceramic casting core comprising:

inserting an insertion portion of the metallic casting core into a receiving portion of the ceramic casting core; and

introducing a slurry between the metallic casting core and the ceramic casting core.

2. The method of claim 1 wherein:

the metallic casting core comprises a refractory metal-based substrate.

3. The method of claim 1 used to form a turbine blade core assembly or a turbine vane core assembly.

4. The method of claim 1 further comprising:

heating the slurry to harden the slurry.

5. The method of claim 1 further comprising:

vibrating the metallic casting core and the ceramic casting core during the introducing.

6. The method of claim 1 wherein:

the inserting is performed with the ceramic casting core in a green state.

7. The method of claim 1 wherein the slurry comprises zircon and aqueous colloidal silica.

8. The method of claim 6 wherein:

the slurry has an aqueous colloidal silica content of 20-30%, by weight, of a zircon content.

9. The method of claim 1 wherein:

the slurry comprises a surfactant.

10. The method of claim 1 wherein the slurry has:

a density of 2.87-2.96 g/cm³;

a pH of 9-10.5; and

a viscosity of 25 ±

2 cP.

11. The method of claim 1 wherein the slurry has:

a density of 2.87-2.96 g/cm³;

a pH of 9-10.5; and

a viscosity of 18-27 cP.

12. A method comprising:

using a slurry comprising zircon and aqueous colloidal silica to secure a metallic casting core to a ceramic casting core.

13. The method of claim 12 further comprising:

heating the slurry to harden the slurry.

14. An apparatus comprising:

means for holding a ceramic casting core;

means for holding a metallic casting core with an insertion portion received in a receiving portion of the ceramic casting core; and

means for vibrating the ceramic casting core and the metallic casting core.

15. The apparatus of claim 14 in combination with:

said ceramic casting core;

said metallic casting core; and

a slurry comprising zircon and aqueous colloidal silica between the metallic casting core and the ceramic casting core and being vibrated by the means for vibrating.

16. The apparatus of claim 14 wherein the means for holding the metallic casting core comprises:

means for adjusting a relative position of the ceramic casting core and the metallic casting core.