当前申请(专利权)人：
SIEMENS ENERGY GLOBAL GMBH & CO. KG
原始申请(专利权)人：
MATERIALS SOLUTIONS LIMITED
当前申请(专利权)人地址：
Otto-Hahn-Ring 6,, 81739, Munich, Germany
摘要：
A method of forming an article from a superalloy by forming a layer of a mixture of at least two metal powders selected such that the mixture has the composition which can form a superalloy containing a gamma prime phase. A layer of the article is formed by locally fusing the powders without diffusion occurring such that the metal powders remain substantially chemically segregated. The complete article is made by repeatedly forming layers and fusing. The complete article is then optionally stress relieved and then heat treated so that diffusion between the powder occurs, thereby forming a superalloy containing a gamma prime phase. The superalloy can be nickel based with one powder being depleted in at least one of aluminium and titanium relative to the superalloy composition and a second powder being rich in this element. Also a method of making a superalloy by mixing a plurality of powders which together can form a superalloy, using the mixture to form and substantially dense article by additive layer manufacturing and then heat treating the article to combine the powders into the superalloy.
权利要求：
Claims
1. A method of forming an article including:
(i) forming a layer of a mixture of at least two distinct metal
powders selected such that when combined they are chemically in
the proportions of a superalloy containing a gamma prime phase
(ii) fusing the powders locally without diffusion to define the
shape of a part of the article such that the materials of the distinct
metal powders remain substantially chemically segregated forming
regions of different chemical composition
(iii) repeating steps (i) and (ii) until the derived article is formed;
and
(iv) heat treating the finished article such that at least one of the
distinct separate materials diffuses to form a gamma prime phase
containing superalloy with the other.
2. A method as claimed in claim 1 wherein the diffusion takes place by solid state diffusion.
3. A method as claimed in claim 1 or claim 2 wherein the article is stress relieved by a heat treatment prior to step (iv).
4. A method as claimed in claim 1 or claim 2 wherein the article is formed on a base plate and is removed therefrom prior to step (iv).
5. A method as claimed in claim 1 of claim 2 wherein it is intended to form a superalloy containing an additive X at a concentration C including:
blending two powders A and B wherein A is the intended bulk
consistent of the superalloy having a concentration of x = (Cx)a selected B allow processing without cracking and wherein powder B is a minor constituent of the intended alloy with a concentration of x = (Cx)s ; blending the powders A and B together so that B is a fraction of the whole such that Cx = f (Cx)s + (1-f) (Cx)a and wherein (Cx)s >(Cx)a.
6. A method as claimed in any one of claims 1 to 5 wherein each powder is melted locally during step (ii).
7. A method of forming an article wherein the powders are of materials less susceptible to stress cracking than the intended superalloy.
8. A method as claimed in any of the preceding claims wherein the intended superalloy is a nickel based superalloy.
9. A method as claimed in any one of the preceding claims wherein the alloy includes an additive x.
10. A method as claimed in claim 9 wherein x is aluminium or titanium or both.
11. A method as claimed in claim 10 wherein x forms more than 3.5% or preferably 4% by weight of the powders.
12. A method as claimed in any one of the preceding claims wherein the article is part of the larger article.
13. A method as claimed in any one of the preceding claims wherein more than 50% by weight of the mixture of powders is formed of metals or alloys which do not crack during ALM processing.
14. A method as claimed in claim 13 wherein the more than 50% powder is Ni, Cr or Fe or a mixture or alloy at least two of them.
15. A method of forming a superalloy including:
(i) selecting and mixing two or more powder components that chemically add to the proportions of the desired superalloy;
(ii) performing ALM processing on the mixture whereby a substantially dense ‘mix’ in the shape of an article that is not the desired superalloy but which is characterised as having a sufficiently low stress not to crack during building or subsequent heat treatment; and
(iii) heat treating the article to form the desired superalloy without cracking.
16. A metal powder for layer processing chemically comprising the constituent components of a gamma prime forming superalloy but with at least one of the constituent components substantially depleted with respect to the relative proportion which would be present in the super alloy.
17. A non-homogenous metal powder mix including a metal powder as claimed in claim 16 and a secondary powder containing the elemental constituent or constituents which are depleted in the first powder.
18. A method as claimed in any one of claims 1 to 15 using the powder of claim 16 or the powder mixture of claim 17.
19. A non-homogenous metal powder mix of claim 17 including a secondary powder containing the elements aluminium and, or titanium.