Components having low aspect ratio

Patent metadata

Field	Value
Publication number	US-11084092-B2
Application number	US-201916665079-A
Country	US
Kind code	B2
Filing date	Oct 28, 2019
Priority date	Oct 27, 2018
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A method of manufacturing a component includes making a preform from a powdered material, the preform having a density in a range from 70 to 95% of theoretical density of the material, The method also includes sintering the preform using a Field Assisted Sintering Technique (FAST) process to produce a component having a density of greater than 97% of the theoretical density of the material. Components, in particular low aspect components, formed by said method are also described.

First claim

The invention claimed is:

1. A method of manufacturing a component comprising:
making a preform from a powdered material, the preform having a density in a range from 70 to 95% of theoretical density of the material; and
sintering the preform using a Field Assisted Sintering Technique (FAST) process to produce a component having a density of greater than 97% of the theoretical density of the material;
wherein the FAST process comprises applying an electric potential across the preform via opposed conductive dies which are arranged to apply pressure simultaneously in order to consolidate the preform; and

wherein the dies for the FAST process are configured to produce a component with a machining allowance of 2% or less;
wherein the preform is made from gravity sintering in ceramic or graphite moulds.

2. The method as claimed in claim 1 , wherein the dies each comprise a die surface and at least one of the die surfaces has been profiled so as to vary in height across the die surface and thereby provide a die cavity defined by a first die separation and a second die separation that is different to the first die separation, and wherein the preform is made with a first portion having a first density in the first die separation prior to the FAST process and a second portion having a second density different to the first density in the second die separation prior to the FAST process.

3. The method as claimed in claim 2 , wherein the die cavity is further defined by a third die separation which is different to the second die separation, and the preform is made with a third portion having a third density which is different to the second density prior to the FAST process, and optionally wherein the third die separation is the same as the first die separation (±3%) and the third density is the same as the first density (±3%) prior to the FAST process.

4. The method as claimed in claim 2 , wherein the first die separation is taller than the second die separation and the preform is made with a first portion having a higher density than the second portion prior to the FAST process, and optionally wherein a (the) third die separation is taller than the second die separation and the preform is made with a third density which is a higher density than the second portion prior to the FAST process.

5. The method as claimed in claim 4 , wherein the component comprises a rotational part, optionally a gear, having a hub which is formed in the first die separation, and a web which is formed in the second die separation, and optionally a rim which is formed in a (the) third die separation.

6. The method as claimed in claim 1 , wherein the component comprises a rotational part having an aspect ratio of 0.5 or less, where the aspect ratio is defined as a height of the component (H) divided by its diameter (D), the height being measured perpendicular to the diameter.

7. The method as claimed in claim 1 , wherein the FAST process is conducted until the component has reached a density of at least 99% of the theoretical density for the material.

8. The method as claimed in claim 1 , wherein the powdered material is a powdered metal material, optionally a weldable metal material.

9. The method as claimed in claim 1 , wherein the powdered material comprises powder having a non-spherical morphology.

10. The method of claim 9 , wherein the material does not comprise a lubricant.

11. The method as claimed in claim 1 , wherein the component is one of a wheel gear, a planet gear, a bevel gear, a ring gear and a flanged ring gear.

Assignees

• Hamilton Sundstrand Corp
• Hamilton Sunstrand Corp

Inventors

• Mironets Sergey
• Wentland William Louis

Classifications

• B22F5/08 Primary

  of toothed articles, e.g. gear wheels; of cam discs · CPC title

• B22F10/28

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title

• B22F3/14 Primary

  simultaneously · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title

• B22F3/02

  Compacting only · CPC title