Abstract: In W—Cu alloy having a homogeneous micro-structure and a fabrication method thereof, the method includes forming mixed powders by mixing tungsten powders with W—Cu composite powders; forming a compact by pressurizing-forming the mixed powders; forming a skeleton by sintering the compact; and contacting copper to the skeleton and performing infiltration. W—Cu alloy having a homogeneous structure fabricated by the present invention shows better performance by being used as a material for high voltage electric contact of a contact braker, a material for heat sink of an IC semiconductor and a shaped charge liner.

Abstract: Disclosed is a method of forming a W—Cu composite powder having a Cu particle surrounded by tungsten by mixing and pulverizing tungsten oxide powder and copper oxide powder using turbular mixing or ball milling, reducing the Cu powder firstly at 200˜400° C. under a hydrogen atmosphere or a reducing gas environment including hydrogen, generating W nuclei on the reduced Cu powder at 500˜700° C., and growing the generated W nuclei at 750˜1080° C. as well as a use of the same for the use of powder injection molding.

Abstract: Disclosed is a tungsten film coating method using tungsten oxide powders including the steps of contacting the tungsten oxide powders with a metal substrate and carrying out thermal reduction treatment thereon at a temperature of at least 650° C. under a hydrogen atmosphere just to coat the tungsten film on the metal substrate. Accordingly, the present invention enables to provide a simple method of coating a tungsten thin film on a metal substrate using the phenomenon of tungsten migration through vapor phase when thermal reduction treatment is carried out on tungsten oxide powders without using previous chemical or physical vapor depositions requiring expensive precision equipments or causing environmental pollution.

Abstract: Disclosed is a densification process of a W—Cu composite material, and more particularly, a sintering method for a W—Cu composite material without exuding of Cu. The sintering method comprises the steps of: holding a W—Cu composite power compact for a certain time at a Cu solid phase temperature or at a temperature just above a melting point and thus inducing a nearly complete densification; and sintering for a short time at a Cu liquidus temperature.

Abstract: In W-Cu alloy having a homogeneous micro-structure and a fabrication method thereof, the method includes forming mixed powders by mixing tungsten powders with W-Cu composite powders; forming a compact by pressurizing-forming the mixed powders; forming a skeleton by sintering the compact; and contacting copper to the skeleton and performing infiltration. W-Cu alloy having a homogeneous structure fabricated by the present invention shows better performance by being used as a material for high voltage electric contact of a contact braker, a material for heat sink of an IC semiconductor and a shaped charge liner.

Abstract: Disclosed is a tungsten film coating method using tungsten oxide powders including the steps of contacting the tungsten oxide powders with a metal substrate and carrying out thermal reduction treatment thereon at a temperature of at least 650° C. under a hydrogen atmosphere just to coat the tungsten film on the metal substrate. Accordingly, the present invention enables to provide a simple method of coating a tungsten thin film on a metal substrate using the phenomenon of tungsten migration through vapor phase when thermal reduction treatment is carried out on tungsten oxide powders without using previous chemical or physical vapor depositions requiring expensive precision equipments or causing environmental pollution.

Abstract: Disclosed is a method of forming a W—Cu composite powder having a Cu particle surrounded by tungsten by mixing and pulverizing tungsten oxide powder and copper oxide powder using turbular mixing or ball milling, reducing the Cu powder firstly at 200˜400° C. under a hydrogen atmosphere or a reducing gas environment including hydrogen, generating W nuclei on the reduced Cu powder at 500˜700° C., and growing the generated W nuclei at 750˜1080° C. as well as a use of the same for the use of powder injection molding.

Abstract: A sintering method for a W--Ni--Mn type heavy alloy, including controlling the deoxidization of tungsten and nickel under an inert atmosphere, changing to a hydrogen atmosphere at above a temperature at which manganese is deoxidized and simultaneously deoxidizing tungsten, nickel and manganese, and sintering by raising the temperature, resulting in the fabrication of a sintered heavy alloy having a 100% relative theoretical density.

Abstract: A method for producing an irregular tungsten/matrix interface in tungsten based heavy alloy is disclosed. The method involves a cyclic heat treatment and resintering at above liquidus temperature for tungsten heavy alloys consisting of 80 to 98 weight % tungsten and remainder of matrix phase. The sintered specimens are cyclically heat treated at above 1000.degree. C. and resintered at liquidus temperature of the matrix phase for one minute to 4 hours at a constant temperature.

Abstract: A fabrication method for a tungsten heavy alloy includes first fabricating a green compact or a sintered body composed of tungsten and other elements except manganese, then putting manganese thereon, and sintering the tungsten heavy alloy with manganese manganese, whereby the formation of pores, which occurs because manganese is oxidized by the deoxidation of oxides existing on the surface of powders of tungsten, nickel and iron is prevented, and a tungsten heavy alloy having a 100% non-theoretical density of 100% is obtained.