Hollow sphere structure of metal-containing tungsten carbide, method for manufacturing the same, method for manufacturing film

Abstract

A hollow sphere structure of metal-containing tungsten carbide (WC-based cermet contains one or two metal elements to form a pseudo binary eutectic) is provided, which includes a porous shell of metal-containing metal carbide surrounding a hollow core. The hollow sphere structure has a diameter of 5 micrometers to 45 micrometers, and the porous shell has a thickness of 0.1 micrometers to 12 micrometers. The metal is cobalt, nickel, or a combination thereof

What is claimed is: 
     
         1 . A method of forming a hollow sphere structure of metal-containing tungsten carbide, comprising:
 wet-dispersing a plurality of metal-containing tungsten carbide particles to form slurry; and   spray drying the slurry to connect the metal-containing tungsten carbide particles for forming the hollow sphere structure of metal-containing tungsten carbide without pure cobalt phase, other decomposition phases, or other oxide phases,   wherein the hollow sphere structure of metal-containing tungsten carbide includes a porous shell of metal-containing tungsten carbide surrounding a hollow core,   wherein the hollow sphere structure has a diameter of 5 micrometers to 45 micrometers, the porous shell has a thickness of 0.1 micrometers to 12 micrometers, and the metal is cobalt, nickel, or a combination thereof,   wherein the other decomposition phases include Co 3 W 3 C, Co 6 W 6 C, Co 7 W 6 , W 2 C, W, graphite, or diamond phase, and   wherein the other oxide phases include WO 3 , WO 2 , CoO, Co 3 O 4  CoO 2 , or CO phase.   
     
     
         2 . The method as claimed in  claim 1 , wherein the porous shell has a plurality of pores, and the pores have a diameter of 0.3 micrometers to 2 micrometers. 
     
     
         3 . The method as claimed in  claim 1 , wherein the metal-containing tungsten carbide particles have a metal formed on tungsten carbide particles. 
     
     
         4 . The method as claimed in  claim 1 , wherein the metal-containing tungsten carbide particles have a diameter of 0.05 micrometers to 0.6 micrometers in the slurry. 
     
     
         5 . The method as claimed in  claim 1 , wherein the metal-containing tungsten carbide particles after spray drying include two grades, wherein Grade I particles have a diameter of 0.05 micrometers to 0.2 micrometers, Grade II particles have a diameter of 0.2 micrometers to 0.6 micrometers, and Grade I particles and Grade II particles have different diameters. 
     
     
         6 . The method as claimed in  claim 5 , wherein Grade I particles and Grade II particles have a weight ratio of 0.08 to 1. 
     
     
         7 . The method as claimed in  claim 1 , wherein the metal and the tungsten carbide particles of the metal-containing tungsten carbide particles have a weight ratio of 10:90 to 14:86. 
     
     
         8 . The method as claimed in  claim 1 , further sintering the hollow sphere structure of metal-containing tungsten carbide to form an irregular shaped structure or a multi-edge angle structure at an inner surface or an outer surface of the porous shell. 
     
     
         9 . A method for manufacturing a film, comprising:
 thermal spraying a hollow sphere structure of metal-containing tungsten carbide to form a metal-containing tungsten carbide film on a substrate,   wherein the hollow sphere structure of metal-containing tungsten carbide includes a porous shell of metal-containing tungsten carbide surrounding a hollow core,   wherein the hollow sphere structure has a diameter of 5 micrometers to 45 micrometers, the porous shell has a thickness of 0.1 micrometers to 12 micrometers, and the metal is cobalt, nickel, or a combination thereof.