Relationship between Composition, Structure, Properties, Thermo-MechanicalProcessing and Ballistic Performance of Tungsten Heavy Alloys

摘要

Traditional tungsten heavy alloys are tungsten--nickel--iron or tungsten--nickel--copper alloys containing 88 to 98% tungsten. Cobalt is also used in these alloys but to a lesser extent. These alloys are produced by blending the elemental powders, pressing billets from the blend and then liquid-phase sintering the billets. These alloys were first developed to provide high density materials that were easy to machine but were developed with little concern for mechanical properties. Initially W-Ni-Cu alloys were most common because the low melting point of copper made these alloys easier to sinter. As the demand for alloys with good mechanical properties increased, a shift occurred from the W-Ni-Cu alloys to the W-Ni-Fe alloys. Processing techniques to consistently produce high quality tungsten heavy alloys were developed. The purpose of this program was to do a thorough study of tungsten heavy alloys and the interrelationship between chemical composition, impurities, thermo-mechanical processing history, structure and ballistic properties. Ballistic testing was to include a wide range of types and sizes ranging from an in house 20mm range to full scale testing.