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|United States Patent||7,896,989|
|Fair , et al.||March 1, 2011|
Methods of making cross sectional, functionally-graded munitions propellants exhibiting various distributions of particle concentrations and burn rate, including having a fast burning core and slower burning outer layer(s). Unlike prior art methods of preparing such munitions, propellants prepared according to our inventive method(s) may be performed substantially as a single extrusion step or as a few processing steps, without requiring the time, expense and/or difficulties that characterized familiar, laminating methods and methods which use multiple extruders. Our inventive method advantageously employs a demixing phenomenon that, prior to our inventive application and teaching, has been considered quite undesirable in the preparation of propellants where uniformity and well-mixedness have been propellant attributes widely sought after.
|Inventors:||Fair; David (Parsippany, NJ), Kalyon; Dilhan M. (Teaneck, NJ), Moy; Sam (Parsippany, NJ), Manole; Leon R. (Great Meadows, NJ)|
The United States of America as represented by the Secretary of the Army
|Filed:||February 11, 2005|
|Application Number||Filing Date||Patent Number||Issue Date|
|60521055||Feb 12, 2004|
|Current U.S. Class:||149/109.6; 149/109.4; 149/17; 149/18; 149/2|
|Current CPC Class:||C06B 21/0008 (20130101); C06B 45/00 (20130101); C06B 45/10 (20130101)|
|Current International Class:||C06B 45/00 (20060101); C06B 45/04 (20060101); C06B 45/06 (20060101); D03D 23/00 (20060101); D03D 43/00 (20060101)|
|Field of Search:||;149/109.6,2,17,18,109.4|
|5009728||April 1991||Chan et al.|
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