USA flag logo/image

An Official Website of the United States Government

Inert-Gas Buffering for Particle Size Separation of Superconductor Precursor…

Award Information

Department of Energy
Award ID:
Program Year/Program:
2006 / SBIR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
Accelerator Technology Corporation
9701 Valley View Dr. College Station, TX 77845-7158
View profile »
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 2
Fiscal Year: 2006
Title: Inert-Gas Buffering for Particle Size Separation of Superconductor Precursor Powders
Agency: DOE
Contract: DE-FG02-05ER84344
Award Amount: $328,600.00


The removal of all particles over a desired micron-scale size threshold from a powder sample is critical to the development of fine-filament, powder-in-tube superconducting wires, for which the final filament size is limited by the largest particles in the precursor powder filling. This project will develop a particle-removal technology that disperses the powder in an aerosol suspension and then passes the dispersed powder through a Stokes-flow geometry, in which the powder particles are separated. The basic approach has been used for several decades for size classification, but never for separation of bulk quantities of powder. In previous work, a slot-geometry impactor was developed and evaluated for bulk separation applications. Phase I improved the earlier process in three respects: (1) dry nitrogen gas was used as the buffer gas rather than air, in order to eliminate contamination of the precursor powders; (2) a fluidized-bed dispersal system was developed to increase mass loading without aggregation; and (3) a boundary-sheet flow of powder-free gas was introduced along the walls of the impactor structure, in order to suppress particle wall interactions that limit large mass loadings. In Phase II, an electron-beam-assisted precipitator will be developed to remove the separated fines from the aerosol flow. The present pressurized inert-gas flow will be converted into a recirculating closed-circuit flow. The slot impactor vane structure will be rebuilt with 1-m-long vanes, and manifolds for supply, exhaust, and boundary flow along the vane structure will be pressure-equalized to assure a uniform Stokes threshold along the extended geometry. Commercial Applications and other Benefits as described by the awardee: In addition to high-performance superconductors, the technology also should be applicable to the separation of particles used in specialty sintered metal and ceramic materials for aerospace and defense, and in consumer products. For ceramics, large particles cause stress concentrations, which cause brittle fracture. For sunscreen, powders utilize Ti2O3, the most effective UV absorber; however, Ti2O3 is also the pigment for white paint, and makes skin appear pasty. By reducing particle size, the powder becomes invisible, while retaining its UV protection capability

Principal Investigator:

Satyananarayanan Seshadri

Business Contact:

Peter M. McIntyre
Small Business Information at Submission:

Accelerator Technology Corporation
9701 Valley View Drive College Station, TX 77845

EIN/Tax ID: 742495994
Number of Employees: N/A
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No