Method for the manufacture of a metal part

• US 9,796,020 B2
• Filed: 01/08/2010
• Issued: 10/24/2017
• Est. Priority Date: 01/12/2009
• Status: Active Grant

• Current Assignee: Metal Addictive Technologies
• Original Assignee: Metec Powder Metal AB
• Inventors: slund, Christer
• Primary Examiner(s): Johnson, Jonathan
• Assistant Examiner(s): KESSLER, CHRISTOPHER S
• Application Number:
  US13/140,162
• Publication Number:
  US 20110256015A1
• Time in Patent Office: 2,846 Days
• Field of Search: 419 28
• CPC Class Codes: B22F 1/102 Metallic powder coated with organic material
• CPC Class Codes: B22F 1/148 Agglomerating
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/04 by applying fluid pressure , e.g. by cold isostatic pressing [CIP]
• CPC Class Codes: B22F 3/087 using high energy impulses, e.g. magnetic field impulses
• CPC Class Codes: B22F 3/1017 Multiple heating or additional steps B22F3/101 takes precedence
• CPC Class Codes: B22F 3/1021 Removal of binder or filler removal of binder from ceramics C04B35/638
• CPC Class Codes: B22F 3/15 Hot isostatic pressing
• CPC Class Codes: B22F 3/16 in successive or repeated steps
• CPC Class Codes: B22F 3/17 by forging
• CPC Class Codes: C22C 33/0257 characterised by the range of the alloying elements

Abstract

A method for the manufacture of a metal part, the method including the steps: a) compacting agglomerated spherical metal powder to a preform, b) debinding and sintering the preform to a part at a temperature not exceeding 1275° C., c) performing one of the following steps: i) compacting the part to a density of more than 95% of the theoretical density, or ii) compacting the part to a density of less than 95% of the theoretical density and sintering the part at a temperature not exceeding 1275° C. to a density of more than 95% of the theoretical density, and d) subjecting the part to hot isostatic pressing at a temperature not exceeding 1200° C. The method provides an industrial process to produce fully dense parts from alloys which normally cannot be produced and still give good impact properties, which is vital for many applications where there alloys are used.

Claims

1. A method for the manufacture of a metal part, the method comprising the sequential steps:

a. compacting agglomerated spherical metal powder to a preform,

b. debinding and sintering the preform to a part at a temperature not exceeding 1275°

C.,

c. compacting the part to a density of more than 95% of the theoretical density, and

d. next without a second sintering step, subjecting the part to hot isostatic pressing at a temperature not exceeding 1200°

C.,

wherein the compacting in step c is performed with high velocity compaction.

2. The method according to claim 1, wherein the high velocity compaction is performed with a ram speed exceeding 2 m/s.

3. The method according to claim 1, wherein the compaction in step a) is performed using a method selected from the group consisting of uniaxial pressing, high velocity pressing and cold isostatic pressing.

4. The method according to claim 1, wherein the compaction in step a) is performed with a pressure not exceeding 1000 N/mm².

5. The method according to claim 1, wherein the metal powder comprises at least one steel selected from the group consisting of tool steel and high speed steel.

6. The method according to claim 1, wherein a soft annealing is performed after step b) in claim 1.