Junhai Liu

US Patent:

6398125, Jun 4, 2002

Filed:

Feb 10, 2001

Appl. No.:

09/780598

Inventors:

Junhai Liu - Auburn AL
Bor Zeng Jang - Auburn AL

Assignee:

Nanotek Instruments, Inc. - Opelika AL

International Classification:

B05B 124

US Classification:

239 13, 239 8, 239 9, 239 10

Abstract:

A two-stage process and apparatus for producing nanometer-scaled powders from a metal, the process including (a) operating a first-stage heating and atomizing device to provide a stream of super-heated fine-sized metal liquid droplets into a chamber of a second-stage atomizing device; (b) operating this second-stage atomizing device by directing an atomizing fluid medium to impinge upon the stream of super-heated metal liquid droplets to further break up the metal liquid droplets into substantially nanometer-sized particles; and (c) cooling these particles to form nanometer-sized solid powders. The first-stage heating and atomizing device preferably includes a twin-wire arc spray device. The second-stage atomizing device preferably includes a vortex jet nozzle.

US Patent:

6401001, Jun 4, 2002

Filed:

Jul 22, 1999

Appl. No.:

09/358871

Inventors:

Bor Z. Jang - Auburn AL
Junsheng Yang - Auburn AL
Junhai Liu - Auburn AL
Lijun Pan - Auburn AL

Assignee:

Nanotek Instruments, Inc. - Opelika AL

International Classification:

G06F 1900

US Classification:

700118, 700 98, 700119, 700120, 700163, 264401, 264512, 264516, 427466, 427470, 427472, 20419215, 2041922, 20429812

Abstract:

A solid freeform fabrication process and apparatus for making a three-dimensional object. The process comprises the steps of (1) positioning a material deposition sub-system a selected distance from a target surface, (2) operating this sub-system to deposit materials onto the target surface by carrying out the sub-steps of (a) operating a multiple-channel powder delivery device for supplying selected powder compositions at a predetermined flow rate to travel toward the target surface and (b) operating a focused energy beam to produce a fusion zone through which the powder particles, preferably in micron or nanometer sizes, are melted while in flight, thereby producing liquid droplets traveling to deposit onto the target surface, and (3) during the material deposition process, moving the deposition sub-system and the target surface relative to one another along selected directions in a plane defined by first and second coordinate directions and in a third direction orthogonal to this plane to form deposition materials into a three dimensional shape. These steps are preferably executed under the control of a computer system. Preferably, the system is also operated to generate a support structure for any un-supported feature of the object.

US Patent:

6444009, Sep 3, 2002

Filed:

Apr 12, 2001

Appl. No.:

09/833727

Inventors:

Junhai Liu - Auburn AL
Bor Zeng Jang - Auburn AL

Assignee:

Nanotek Instruments, Inc. - Opelika AL

International Classification:

B22F 908

US Classification:

75332, 75338

Abstract:

A two-stage method for producing ultra-fine and environmentally stable solid powders from a metal composition including a reactive alloying element. The method includes the steps of: (a) operating a first-stage heating and atomizing means to provide a stream of super-heated fine-sized metal liquid droplets into a chamber of a second-stage atomizing means with the second-stage atomizing means containing a supply of an atomizing fluid medium composed of at least a reactive gas and an inert gas at a predetermined proportion; (b) operating the second-stage atomizing means by directing the atomizing fluid medium into the chamber to impinge upon the stream of super-heated metal liquid droplets to further break up the metal liquid droplets into ultra-fine particles and to allow the reactive gas to react with the reactive alloying element for forming a protective layer on the exterior surface of the particles; and (c) cooling the particles to form ultra-fine solid powders.

US Patent:

6780368, Aug 24, 2004

Filed:

Apr 10, 2001

Appl. No.:

09/829548

Inventors:

Junhai Liu - Auburn AL
Bor Z. Jang - Auburn AL

Assignee:

Nanotek Instruments, Inc. - Fargo ND

International Classification:

B29C 3508

US Classification:

264401, 264405, 264497, 264482, 264483, 264485, 264488, 264489, 264494, 264112, 264308

Abstract:

A freeform fabrication method for fabricating a 3-D multi-material or multi-color object from successive layers of a primary body-building powder, at least a modifier material and a binder powder in accordance with a computer-aided design of the object. The method including: (a) providing a work surface; (b) feeding a first layer of the primary body-building powder to the work surface; (c) operating an electrophotographic powder deposition device to create a images of at least a modifer powder and a binder powder in accordance with this design; (d) transferring these powder images in a desired sequence to the first layer of a body-building powder; (e) applying energy sources to fuse the binder powder for bonding the powder particles to form a first cross-section of the object; (f) repeating the feeding, operating, transferring, and applying steps to build a second and successive layers of materials in a layer-wise fashion for forming the multiple-layer, multi-material object; and (g) removing un-bonded powder particles, causing the 3-D object to appear.

US Patent:

20020093115, Jul 18, 2002

Filed:

Jan 12, 2001

Appl. No.:

09/760441

Inventors:

B. Jang - Auburn AL, US
Junhai Liu - Auburn AL, US
Liangwei Wu - Auburn AL, US

International Classification:

B29C035/08

US Classification:

264/113000, 425/073000, 425/140000, 425/162000, 425/174400, 264/401000, 264/463000, 264/494000, 264/040100

Abstract:

A method and related apparatus for fabricating a three-dimensional object in accordance with a computer-aided design of the object in a layer-by-layer but not point-by-point fashion. The method includes the following steps: (a) providing a work surface lying substantially parallel to an X-Y plane of an X-Y-Z Cartesian coordinate; (b) feeding a first layer of a first powder to this work surface and spraying a photo-curable adhesive to this powder; (c) directing a programmable planar light source to predetermined areas of the first layer to at least partially cure the adhesive and bond the powder particles together in these areas for the purpose of forming the first cross-section of this object; (d) feeding a second layer of a second powder onto the first layer, spraying the photo-curable adhesive onto the second powder layer, and directing a programmable planar light source to predetermined areas of the second layer to at least partially cure the adhesive and bond the powder particles together in these areas for the purpose of forming the second cross-section of the object; (e) repeating the feeding, spraying and directing steps to build successive layers along the Z-direction in a layer-wise fashion in accordance with the design for forming multiple layers of the object; and (f) removing un-bonded powder particles and un-cured adhesive to reveal the 3-D object.

US Patent:

20020149137, Oct 17, 2002

Filed:

Apr 12, 2001

Appl. No.:

09/833825

Inventors:

Bor Zeng Jang - Auburn AL, US
Junhai Liu - Auburn AL, US
Liangwei Wu - Auburn AL, US

International Classification:

B29C067/02

US Classification:

264/494000, 264/040100, 425/174400, 425/140000

Abstract:

A method and related apparatus for fabricating a three-dimensional object in accordance with a computer-aided design of the object in a layer-by-layer but not point-by-point fashion. The method includes the following steps: (a) providing a work surface; (b) feeding a first layer of a photo-curable material mixture to this work surface, the mixture including a primary body-building powder material and a photo-curable adhesive; (c) directing a programmable planar light source to predetermined areas of the first layer to at least partially cure the adhesive and bond the powder particles together in these areas for the purpose of forming the first cross-section of this object; (d) feeding a second layer of the material mixture onto the first layer and directing a programmable planar light source to predetermined areas of the second layer to at least partially cure the adhesive and bond the powder particles together in these areas for forming the second cross-section of the object; (e) repeating the feeding and directing steps to build successive layers of the material mixture in a layer-wise fashion in accordance with the design for forming multiple layers of the object; and (f) removing un-bonded powder particles and un-cured adhesive to reveal the 3-D object.

US Patent:

20060090593, May 4, 2006

Filed:

Nov 3, 2004

Appl. No.:

10/980708

Inventors:

Junhai Liu - North Huntingdon PA, US

International Classification:

C22C 1/05

US Classification:

075252000, 427199000

Abstract:

The invention relates to an adaptation of the cold spray process to provide a method of coating fine metal particles, including aluminum and copper, onto a work piece. In one embodiment, the invention is a metal agglomerated hard sphere composition capable of providing about a 1 micron or thicker coating of a metal on a work piece in a cold spray process. In another embodiment the invention is a method of coating metal particles, including metal particles having a particle size of about 0.01 to about 10 micron, onto a work piece. The method of the invention circumvents many of the problems associated with cold spray processing of very fine particles.

US Patent:

62807846, Aug 28, 2001

Filed:

Feb 10, 2000

Appl. No.:

9/501648

Inventors:

Junsheng Yang - Auburn AL
Liangwei Wu - Auburn AL
Junhai Liu - Auburn AL

Assignee:

Nanotek Instruments, Inc - Opelika AL

International Classification:

A23P 100
B29C 3100

US Classification:

426231

Abstract:

A freeform fabrication method for making a three-dimensional food object from a design created on a computer, including: (a) providing a support member by which the object is supported while being constructed; (b) operating a material dispensing head for dispensing a strand of food composition in a fluent state with this food composition comprising a volatile ingredient; (c) operating a material treatment device disposed near the strand of food composition to at least partially remove the volatile ingredient for causing the food composition to achieve a rigid state in which the food composition is built up in a 3-D shape of the object; and (d) operating control devices for generating control signals in response to coordinates of the design of the object and controlling the position of the dispensing head relative to the support member in response to the control signals to control dispensing of the food composition for constructing the object while supported with the support member. The method optionally includes an additional step of removing the residual volatile ingredient from the resulting 3-D shape or applying a heat treatment to the 3-D shape upon construction of this shape.