US 9,322,090 B2Granted

Components formed by controlling grain size in forged precipitation-strengthened alloys

AssigneeGeneral Electric Company

InventorsGeorge Albert Goller, Raymond Joseph Stonitsch, Richard DiDomizio

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Abstract

Components and methods of processing such components from precipitation-strengthened alloys so that the components exhibit desirable grain sizes following a supersolvus heat treatment. The method includes consolidating a powder of the alloy to form a billet having an average grain size. The billet is then forged at a temperature below the solvus temperature to form a forging having an average grain size of not coarser than the grain size of the billet. The billet is then forged at a total strain of at least 5%, after which at least a portion of the forging is heat treated at a temperature below the solvus temperature to pin grains within the portion. The entire forging can then be heat treated at a temperature above the solvus temperature of the alloy without coarsening the grains in the portion.

Claims20

Dependent claims

An article having first and second portions, the article being produced by a method comprising:

forming a powder of a precipitation-strengthened iron-based or nickel-based superalloy having a solvus temperature
consolidating the powder at a temperature below the solvus temperature of the superalloy to form a billet having an average grain size;
forging the billet at a temperature below the solvus temperature of the superalloy to form a forging comprising the first and second portions of the article, the forging having an average grain size of not coarser than the average grain size of the billet, the billet being forged so as to achieve a total strain of at least 5%;
heat treating at least the first portion of the forging, but not the second portion of the forging, at a temperature below the solvus temperature of the superalloy to pin grains within the first portion;
heat treating the forging in its entirety at a temperature above the solvus temperature of the superalloy to solution precipitates in the forging without coarsening the grains in the first portion, wherein grains in the second portion are coarsened to an average grain size of coarser than the average grain size of the billet;
and
cooling the forging, wherein the average grain size within the first portion is within 1 or 2 ASTM sizes of the average grain size of the billet.

4 more elements

A disk for a land-based gas turbine engine, the disk having a rim portion and a hub portion and being produced by a method comprising:

forming a powder of a precipitation-strengthened nickel-based superalloy having a solvus temperature;
hot isostatic pressing the powder at a temperature below the solvus temperature of the superalloy to form a billet having an average grain size of ASTM 8 or finer and a density of at least 99% of theoretical;
forging the billet at a temperature below the solvus temperature of the superalloy to form a forging having an average grain size of ASTM 8 or finer, the billet being forged so as to achieve a total strain of at least 5%;
heat treating a hub portion of the forging but not a rim portion of the forging, the heat treating being performed at a temperature below the solvus temperature of the superalloy to pin grains within the hub portion to an average grain size of ASTM 8 or finer;
heat treating the forging in its entirety at a temperature above the solvus temperature of the superalloy to solution precipitates in the forging, the grains in the rim portion being coarsened to an average grain size of coarser than ASTM 8 and the grains in the hub portion having an average grain size of ASTM 8 or finer;
aging the forging to form precipitates in the forging;
cooling the forging, wherein the average grain size within the hub portion is ASTM 8 or finer and the average grain size within the second portion is ASTM 2 to 7;
and
machining the forging to produce the disk.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/171,901Filed 4 Feb 2014 · division
Priority: 5 May 2011
Published: US 2015/0284832 A18 Oct 2015
Granted: 26 Apr 2016
Term ends: Not estimatedThe source records don’t support an estimate.

Classification23 codes

C22F 1/10
Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working: of nickel or cobalt or alloys based…
B21J 1/06
Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling: heating or cooling methods or…
B21K 1/32
Wheels; discs: discs, e.g. disc wheels
B22F 3/15
Simultaneously: hot isostatic pressing

Family

Application13/101,217Parent of this division · filed 5 May 2011
US 2015/0284832 A1Pre-grant publication · published 8 Oct 2015
US 8,679,269 B2Parent of this division
US 2012/0282106 A1Published application
US 9,322,090 B2This patent

From the US filing history. Foreign family members aren’t listed.