当前申请(专利权)人地址：
Advanced manufacturing Park, Brunel Way, ROTHERHAM, S60 5WG , United Kingdom
摘要：
A metal component is formed by building a mould 501 around a sacrificial model, removing the model, placing metal powder 108 in the mould 501 while vibrating and then melting the powder 108 in a sub-atmospheric pressure. The mould 501 comprises a section (502, Fig. 5) in which the component is formed and a feeder section 503, with the mould 501 being filled with powder 108 so that when molten the height 804 of molten metal 801 in the feeder section 503 is more than twice the height 803 of the component section (502, Fig. 5). A gas porous projection (505, Fig. 6) extends into the feeder section 503 along its length whereby gases can escape from the molten metal 801. Additional molten metal is fed into the mould 501 via tubes as it solidifies. The mould 501 can be ceramic formed by sequentially adding wet slurry layers and dry stucco layers to the model.
权利要求：
Claims
What we claim is:
1. A method of forming a metal component, in which a feed material is initially in a powdered state and a solid component is formed by the application of heat, characterized by performing the steps of:
creating a sacrificial positive model of a component;
building a negative mould around said positive model from a material having a melting point higher than the melting point of the metal from which the component is to be formed;
removing said sacrificial positive model from said negative mould;
deploying said feed material of metal powder into said mould; and
heating said metal powder to a temperature higher than the melting point of said metal powder so as to cause said metal powder to melt within the mould.
2, The method of claim 1, characterized in that said sacrificial positive model is created by machining a material, injecting a wax or by an additive manufacturing process.
3. The method of claim 1 or claim 2, characterized in that said material having a melting point higher than the melting point of the metal from which the component is formed is a ceramic.
4. The method of claim 3, characterized in that said step of building said negative mould consists of adding a plurality of layers.
5. The method of claim 4, characterized in that said layers are added as an alternating wet slurry layer followed by a substantially dry stucco layer.
6. The method of claim 5, characterized in that said alternating slurry layers and stucco layers contain substantially similar ceramic material.
7. The method of any of claims 1 to 6, characterized in that during the deploying of said feed material into the mould, a degree of vibration is introduced to facilitate the dispersal of said feed material within the mould.
8. The method of any of claims 1 to 7, characterized in that said heating step is performed while the mould is retained within a chamber and the pressure within said chamber is reduced to a pressure below atmospheric pressure.
9. The method of any of claims 1 to 8, characterized by including feeding tubes containing additional liquefied metal for feeding into said mould as said mould cools and the metal contained within said mould contracts.
10. Apparatus for forming a metal component, in which a feed material is initially in a powdered state and a solid component is formed by the application of heat, characterized in that:
a sacrificial positive model of a component is created;
a negative mould is built around said positive model from a material having a melting point higher than the melting point of the metal from which the material is formed: and
said sacrificial positive model is removed from said negative mould, the apparatus comprising:
a deploying device for deploying the feed material of metal powder into the mould: and
a heating system for heating said metal powder to a temperature higher than the melting point of said metal powder so as to cause said metal powder to melt within the mould.
11. The apparatus of claim 10, characterised by building devices configured to build said negative mould from a ceramic material.
12. The apparatus of claim 11, characterized in that said building devices build the ceramic mould by adding a plurality of layers.
13. The apparatus of any of claims 10 to 12, characterized in that said mould defines a component section corresponding to the metal component being produced and a feeder section for feeding molten metal into said component section, wherein said powdered metal is poured into said mould such that the melted powdered metal in said feeder section extends up to a head level.
14. The apparatus according to claim 13, characterized in that the difference in height between the top of said component section and said head level is more than twice the height of said component section.
15. The apparatus of claim 13 or claim 14, characterized in that said feeder has an open end and said powdered metal is poured into said mould through said open end.
16. The apparatus of any of claims 13 to 15, characterized in that the feeder is arranged to have an inwardly extending element.
17. The apparatus of claim 16, wherein said inwardly extending element is porous to gasses, to provide a means for allowing gas trapped within the molten metal in the feeder to escape.
18. The apparatus of any of claims 9 to 17, including pressure reduction apparatus configured to reduce the pressure in said chamber to a
pressure below atmospheric pressure.
19. A method of forming a metal component substantially herein described, with reference to Figures 1 to 4.
20. Apparatus for forming a metal component substantially herein described with reference to Figures 5 to 12.