MANUFACTURING METHOD

Abstract

There is provided a method of manufacture of a component from multiple materials, and a consolidated component formed thereby. The method includes the steps of forming a component body comprising a first material, the component body defining a cavity, filling at least a portion of the cavity with a second material, and performing hot isostatic pressing of the component body and second material to form a consolidated component. The process offers a reduced-complexity, reduced-part-count method of manufacture for components formed of multiple materials.

Claims

1. A method of manufacturing a component from multiple materials including the steps of: forming a component body comprising a first material, the component body defining a cavity; filling at least a portion of the cavity with a second material; and performing hot isostatic pressing of the component body and second material to form a consolidated component.

2. The method of manufacturing according to claim 1 wherein the second material is a powder material.

3. The method according to claim 1 comprising forming the component body using an additive manufacturing process.

4. The method according to claim 3 wherein the additive manufacturing process is one of laser/electron beam melting/sintering, powder bed fusion, 3D printing, selective laser sintering/melting, a blown powder process, direct laser deposition, freeform manufacture, or additive layer manufacturing.

5. The method according to claim 1 comprising forming the component body by machining.

6. The method according to claim 1 comprising forming the component body comprising one or more sacrificial portions which partly define the cavity.

7. The method according to claim 6 further comprising removing the sacrificial portion(s) of the component body after the step of performing hot isostatic pressing.

8. The method according to claim 1 comprising forming the component body as a net or near-net shape component.

9. A consolidated component formed by the method according to claim 1.

Description

DESCRIPTION OF THE DRAWINGS

[0030] Embodiments will now be described by way of example with reference to the accompanying drawings in which:

[0031] FIGS. 1A-1D show selected schematic sections taken throughout a method of manufacture of a valve with hard facing;

[0032] FIGS. 2A-2D show selected schematic sections taken throughout a method of manufacture of a pipe with internal cladding;

[0033] FIGS. 3A-3D show selected schematic sections taken throughout a method of manufacture of an artificial hip joint having a hard-wearing coating material; and

[0034] FIGS. 4A-4C show 3D rendered versions of the articles shown in FIG. 3.

DETAILED DESCRIPTION

[0035] FIG. 1 shows selected schematic sections taken throughout a method of manufacture of a valve with hard facing.

[0036] FIG. 1A shows the step of forming the component body 101, here a valve body using an additive manufacturing process of laser melting/sintering. In a manner well-known to those in the art, a powder bed 103 is placed on a supporting baseplate 105, and selected areas of the powder bed as defined by a 3D product model are melted using a laser to form a solid component body. After the additive manufacture process is complete, the solid component body is surrounded by un-melted powder which is subsequently removed once the melting/sintering process is complete to leave the component body as shown in FIG. 1B. The powder is typically vacuumed away, however where the internal features are complex, the component may be manipulated to encourage the powder to flow out. For very complex parts, ultrasonic wash stations may be used. The component body is here made entirely from grade 316 stainless steel.

[0037] The component body 101 is formed to define a cavity 107. Here, the component body 101 is formed to be a near-net shape component comprising sacrificial portions 109. In the present example, the cavity in the component body is partially defined by these sacrificial portions of the component body, and partially defined by non-sacrificial portions. The shape of the cavity is selected so as to control deformation during the hot isostatic pressing step.

[0038] In FIG. 1C, the cavity 107 is part-filled with a powder 111 of a second material (here a material from the Tristelle alloy family) via an opening 113. The level of filling is selected as appropriate given the desired final design of the component. Here, because the incorporation of the second material into the component is for the purpose of producing a hard-facing on a valve, it is not necessary to fill the entire cavity. Rather, by part-filling the cavity, the process can achieve a more economical usage of raw materials.

[0039] The entire component then undergoes a hot isostatic pressing cycle, during which the second material powder 111 densifies and bonds to the component body 101 at the cavity walls, thereby forming a consolidated component 120.

[0040] Post-densification, the consolidated component is further processed (e.g. machined) to remove sacrificial portions 109 of the component body, along with excess second material. The final product, shown in FIG. 1D is a consolidated component comprising a valve body portion 115 of a first material having an integrated hard facing 117 of a second material at the location of the original cavity.

[0041] FIG. 2 shows selected schematic sections taken throughout a method of manufacture of a pipe with internal cladding. The method of manufacture is similar to that described above in relation to manufacture of a valve with hard facing. Initially, a component body 201 of a first material (e.g. mild steel) is fabricated using a method of additive manufacture from a powder bed 203 supported by a baseplate 205. Here, the component body 201 is formed to define an annular cavity 207 around the central shaft of the pipe. The cavity has an opening 213 through which a powder 211 of a second material (e.g. stainless steel) is inserted to fill the cavity. The component body is formed such that the cavity 207 is partially defined by sacrificial portions 209 of the component body (here the radially inner cavity wall), and partially defined by non-sacrificial portions (here the radially outer cavity wall).

[0042] In the same manner as discussed in relation to the previous example, once the cavity 207 has been filled with powder 211 the component undergoes a hot isostatic pressing cycle to form the consolidated component 220 followed by removal of sacrificial portions of the component body. The final product is a consolidated component comprising a pipe body portion 215 of a first material having exposed integrated interior surface cladding 217 of a second material at the location of the original cavity.

[0043] FIGS. 3 and 4 show selected schematic sections taken throughout a method of manufacture of an artificial hip joint having a hard-wearing coating material covering a part of the joint. FIGS. 4A and 4B are 3D rendered equivalents of a component as shown in FIG. 3B. FIG. 4C is a 3D rendered equivalent of FIG. 3D. The method of manufacture is similar to that described above in relation to manufacture of a valve with hard facing. Initially, a component body 301 of a first material is fabricated using a method of additive manufacture from a powder bed 303 supported by a baseplate 305. Here, the component body 301 is formed to define an approximately hemispherical cavity 307 surrounding the ball joint portion of the artificial hip joint. An opening 313 is provided at the centre of the hemispherical cavity, and the cavity is filled with powder 311 of a second material through said opening. The component body is formed such that the hemispherical cavity 307 is partially defined by a radially outer shell which is a sacrificial portion 309 of the component body, and partially defined by a non-sacrificial ball-joint portion of the component body.

[0044] In the same manner as discussed in relation to the previous example, the component undergoes a hot isostatic pressing cycle to form the consolidated component 320 followed by removal of sacrificial portions of the component body. The final product is a consolidated component comprising a hip joint body portion 315 of a first material having an integrated surface covering 317 of a second material at the location of the original cavity.

[0045] It will be understood that the disclosure is not limited to the embodiments above-described and various modifications and improvements can be made without departing from the concepts described herein. Except where mutually exclusive, any of the features may be employed separately or in combination with any other features and the disclosure extends to and includes all combinations and sub-combinations of one or more features described herein.