Method for producing an article having a cavity

Patent metadata

Field	Value
Publication number	US-10040114-B2
Application number	US-201013258900-A
Country	US
Kind code	B2
Filing date	Feb 12, 2010
Priority date	Apr 24, 2009
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

A method for producing an article (1) having a cavity (4), in which method a mould (2) provided with a core (3) is filled with article material, the article material is hardened around the core (3) to form the article (1), and the core (3) is removed from the solidified article (1). The core (3) is made of yttria tetragonal zirconia polycristal material (Y-TZP) or partially stabilized zirconium (PSZ), and after the hardening phase the core (3) is exposed to a steam atmosphere, after which the core (3) is removed from the article (1).

First claim

The invention claimed is:

1. A method for producing an article having a cavity, the method comprising:
providing a mold with a core made of yttria tetragonal zirconia polycristal material (Y-TZP), wherein the core is sintered;
filling the mold with article material;
hardening the article material around the core to form the article;
after the hardening, exposing the core to a steam atmosphere; and
after said exposing, removing the core from the article.

2. The method according to claim 1 , wherein the core is exposed to a steam atmosphere at a temperature of at least 100° C.

3. The method according to claim 2 , wherein the core is exposed to a steam atmosphere at a temperature of at least 200° C.

4. The method according to claim 1 , wherein the core is exposed to steam atmosphere for at least 1 hour.

5. The method according to claim 4 , wherein the core is exposed to steam atmosphere for at least 3 hours.

6. The method according to claim 1 , wherein the mold is filled with molten metal material.

7. The method according to claim 1 , wherein the mold is filled with metal powder, which is hardened about the core by isostatic pressing process.

Assignees

• Laine Jarkko Ilari
• Waertsilae Finland Oy

Inventors

• Laine Jarkko Ilari

Classifications

• B22F5/10

  of articles with cavities or holes, not otherwise provided for in the preceding subgroups · CPC title

• B22C7/023

  Patterns made from expanded plastic materials · CPC title

• B22F2998/00

  Supplementary information concerning processes or compositions relating to powder metallurgy · CPC title

• B22D29/001

  Removing cores · CPC title

• B22C9/10 Primary

  Cores; Manufacture or installation of cores {(breaker cores B22C9/084)} · CPC title