Powder feeder for material deposition systems

Abstract

A method and apparatus for embedding features and controlling material composition in a three-dimensional structure (130) is disclosed. The invention enables the control of material characteristics, within a structure (130) made from a plurality of materials, directly from computer renderings of solid models of the components. The method uses stereolithography and solid model computer file formats to control a multi-axis head (480) in a directed material deposition process (123). Material feedstock (126, 127) is deposited onto a pre-heated substrate (19). Depositions (15) in a layer-by-layer pattern, defined by solid models (141, 146), create a three-dimensional article having complex geometric details. Thermal management of finished solid articles (250-302), not available through conventional processing techniques, is enabled by embedded voids (152) and / or composite materials (126, 127), which include dissimilar metals (210, 216). Finished articles control pressure drop and produce uniform coolant flow and pressure characteristics. High-efficiency heat transfer is engineered within a solid structure by incorporating other solid materials with diverse indexes. Embedding multi-material structures (132, 134) within a normally solid component (141) produces articles with diverse mechanical properties. Laser and powder delivery systems (420, 170) are integrated in a multi-axis deposition head (480) having a focused particle beam (502) to reduce material waste.

Description

CROSS-REFERENCES TO RELATED PATENT APPLICATIONS & CLAIMS FOR PRIORITY [0001] This application is a continuation application of U.S. patent application Ser. No. 10 / 128,658, entitled “Forming Structures from CAD Solid Models”, filed on Apr. 22, 2002, which is a continuation-in-part application of U.S. patent application Ser. No. 09 / 568,207, now U.S. Pat. No. 6,391,251, entitled Forming Structures from CAD Solid Models, filed on May 9, 2000, which claims the benefit of the filing of U.S. Provisional Patent Application Ser. No. 60 / 143,142, entitled “Manufacturable Geometries for Thermal Management of Complex Three-Dimensional Shapes”, filed on Jul. 7, 1999. The specifications and claims of all of the above references are hereby incorporated herein by reference.FIELD OF THE INVENTION [0002] The present invention relates to the field of direct material deposition processes which allow complex structures to be fabricated efficiently in small lots to meet stringent requirements of a rapidly...

AI Technical Summary

Benefits of technology

[0025] Heating the substrate and the deposition produces parts with accurate dimensions by eliminating warping of the substrate and deposition. A prescribed temperature profile is used for processing tempered material. A temperature profile for heat treating may be used to enhance the mechanical properties of the part by ensuring the correct material microstructure during processing.

Problems solved by technology

The process then was very inaccurate, and the choice of materials was limited.

Moreover, there is a potential for making very complex parts of either solid, hollow or latticed construction.

Such a deposition process would seem to have substantial problems of warping and distorting the deposited layers because of incomplete melting of feedstock material.

The methods described are very specific to cermets and do not employ solid models and automated processes.

It is not a direct fabrication method for three-dimensional objects with graded or multiple material structures.

The method does not create structures of gradient material.

The patent describes the advantages of gradient materials, however, it does not discuss the use of solid models to achieve the shape of the gradient article.

The problem of providing a method and apparatus for optimum control of fabrication of articles having a fully dense, complex shape, made from gradient or compound materials from a CAD solid model, is a major challenge to the manufacturing industry.

Creating complex objects with desirable material properties, cheaply, accurately and rapidly has been a continuing problem for designers.

Producing such objects in high-strength stainless steel and nickel-based super alloys, tool steels, copper and titanium has been even more difficult and costly.

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