Abrasive Preforms and Manufacture and Use Methods

Patent metadata

Field	Value
Publication number	US-2016003066-A1
Application number	US-201514755350-A
Country	US
Kind code	A1
Filing date	Jun 30, 2015
Priority date	Jul 2, 2014
Publication date	Jan 7, 2016
Grant date	—

Abstract

A method for applying an abrasive comprises: applying, to a substrate, the integral combination of: a self-braze material; and an abrasive embedded in the self-braze material; and securing the combination to the substrate.

First claim

1 . A method for applying an abrasive, the method comprising:
applying, to a substrate, the integral combination of:
a self-braze material; and
an abrasive embedded in the self-braze material; and
securing the combination to the substrate.

2 . The method of claim 1 wherein:
the securing comprises heating to cause the self-braze material to braze to the substrate or an intervening component.

3 . The method of claim 1 wherein the applying comprises applying an assembly of the combination and at least one additional braze material layer, said additional braze material layer lacking abrasive.

4 . The method of claim 3 wherein the assembly further comprises a cast intermediate layer.

5 . The method of claim 3 wherein the self-braze material and the at least one additional braze material layer each comprise a mixture of alloys of different melting points.

6 . The method of claim 1 wherein:
the securing comprises heating and leaves at least a portion of the self-braze material with a composition comprising, in weight percent:
cobalt 2.5-13.5;
chromium 12-27;
aluminum 5-7;
yttrium 0.0-1.0;
hafnium 0.0-1.0;
silicon 1.0-3.0;
tantalum 0.0-4.5;
tungsten 0.0-6.5;
rhenium 0.0-2.0;
molybdenum 0.1-1.0; and
the balance nickel.

7 . The method of claim 6 wherein:
said portion of the self-braze material has said composition comprising, in weight percent:
cobalt 2.5-13.5;
chromium 12-27;
aluminum 5-7;
yttrium 0.0-1.0;
hafnium 0.0-1.0;
silicon 1.0-3.0;
tantalum 2.0-4.5;
tungsten 2.0-6.5;
rhenium 0.0-2.0;
molybdenum 0.1-1.0; and
the balance nickel.

8 . The method of claim 6 wherein:
said composition has no more than 1.0 weight percent of any other individual element.

9 . The method of claim 6 wherein:
said composition has no more than 3.0 weight percent of all other individual elements combined.

10 . The method of claim 1 wherein:
the abrasive comprises cubic boron nitride.

11 . The method of claim 10 wherein:
a weight ratio of the abrasive to the self-braze material is from 1:2 to 2:1.

12 . The method of claim 1 wherein:
a weight ratio of the abrasive to the self-braze material is from 1:2 to 2:1.

13 . The method of claim 1 wherein the self-braze material comprises a sintered mixture of:
at least one first alloy of low melting point relative to the substrate; and
at least one second alloy of high melting point relative to the first alloy.

14 . The method of claim 1 wherein the combination comprises said abrasive in a matrix of:
at least one first alloy of low melting point relative to the substrate; and
at least one second alloy of high melting point relative to the first alloy.

15 . The method of claim 14 wherein:
the at least one first alloy comprises about 21.25-22.75 chromium, about 5.7-6.3 aluminum, about 11.5-12.5 cobalt, about 5.7-6.3 silicon, boron in an amount no greater than 1.0 weight percent, and a balance of nickel plus impurities if any; and
the at least one second alloy comprises about 4.75-10.5 chromium, about 5.5-6.7 aluminum, up to about 13 weight percent cobalt, about 3.75-9.0 tantalum, about 1.3-2.25 molybdenum, about 3.0-6.8 tungsten, about 2.6-3.25 rhenium, up to about 0.02 boron, about 0.05-2.0 hafnium, up to about 0.14 carbon, up to about 0.35 zirconium, and a balance of nickel plus impurities if any.

16 . The method of claim 15 wherein:
a boron content of the first alloy is at least 0.30 weight percent greater than a boron content, if any, of the second alloy.

17 . The method of claim 15 wherein:
the at least one first alloy comprises no more than 1.0 weight percent of any other individual element; and
the at least one second alloy comprises no more than 1.0 weight percent of any other individual element.

18 . The method of claim 1 wherein:
the combination has a characteristic thickness T 2 of 0.20-2.50 millimeters.

19 . The method of claim 1 wherein:
the applied combination consists of the self-braze material and the abrasive.

20 . The method of claim 1 further comprising forming the combination by:
mixing the abrasive and powders of at least two different alloys; and
sintering the mixture.

21 . The method of claim 20 wherein the at least two different alloys comprise:
at least one first alloy of low melting point relative to the substrate; and
at least one second alloy of high melting point relative to the first alloy.

22 . An article formed by the method of claim 1 .

23 . The article of claim 22 being a turbine blade and wherein the combination is applied to a tip surface of an airfoil of the blade.

24 . An article comprising:
a metallic substrate; and a layer secured to the substrate and at comprising a matrix material least partially embedding an abrasive,
wherein:
at least a portion of the matrix material has a composition comprising, in weight percent:
cobalt 2.5-13.5;
chromium 12-27;
aluminum 5-7;
yttrium 0.0-1.0;
hafnium 0.0-1.0;
silicon 1.0-3.0;
tantalum 0.0-4.5;
tungsten 0.0-6.5;
rhenium 0.0-2.0;
molybdenum 0.1-1.0; and
the balance nickel plus impurities, if any.

25 .- 27 . (canceled)

28 . A braze preform comprising the integral combination of:
a self-braze material; and an abrasive embedded in the self-braze material.

29 .- 32 . (canceled)

Assignees

• United Technologies Corp

Inventors

• Stratton Eric W
• Minor Michael J

Classifications

• C22C19/055

  with the maximum Cr content being at least 20% but less than 30% · CPC title

• B23K35/0255

  for use in welding (B23K35/0205 takes precedence) · CPC title

• B23K35/304

  with Cr as the next major constituent · CPC title

• B23K1/0018

  Brazing of turbine parts · CPC title

• F01D11/122

  with erodable or abradable material (blades having cutting or grinding tips F01D5/20) · CPC title