Method for manufacturing a component of a rotating machine
A method for manufacturing a component of a rotating machine comprises the steps of forming a structural inner portion by additive manufacturing from a first material; covering the structural inner portion with a protective outer portion made of a second material; the first material has a melting point higher than a second material.
1. A component for a rotating machine comprising:
a structural inner portion manufactured by additive manufacturing and made from a first material, the inner portion defined by a lattice structure comprising a plurality of cells, each cell formed by a repeating set of nodes and beams, where adjacent nodes are joined by beams;
a protective outer portion covering the structural inner portion and made of a second material, wherein the first material has a melting point higher than the second material and the component is a blade of a gas turbine.
2. The component according to claim 1 , wherein at least two mechanical properties of the inner portion are higher than that of the outer portion.
3. The component according to claim 1 , wherein the mechanical properties are tensile strength and creep resistance.
4. The component according to claim 1 , wherein said second material has a higher resistance to corrosion and oxidation than the first material at high temperatures.
5. The component according to claim 4 , wherein said high temperatures are higher than 1000° C.
6. The component according to claim 5 , wherein the outer portion is made by hot isostatic pressuring.
7. The component according to claim 1 , wherein the second material comprises a nickel aluminum alloy.
8. The component according to claim 1 , wherein the first material comprises a predominant weight of a refractory metal.
9. The component according to claim 8 , wherein the refractory metal comprises tungsten or a tungsten alloy or a molybdenum alloy.
10. The component according to claim 6 , wherein the structural inner portion is a vessel configured to receive a powder of the second material and withstand pressures reached during the hot isostatic pressuring.
11. The component according to claim 1 wherein the outer portion covers entirely the inner portion.
12. The component according to claim 1 , wherein the first material comprises a predominant weight of a eutectic metal.
13. The component according to claim 1 , wherein the first material is a silicide-based composite material and the second material comprises a nickel aluminum alloy.
14. The component according to claim 13 , wherein the silicide-based composite material comprises a silicide, Si3N4 and at least an oxide.