Application of metallic glass and metallic glass thin film coating on the sharpness enhancement of cutting tools

Abstract

A cutting tool having a metallic glass thin film (MGTF) coated thereon, a metallic glass cutting tool, and methods of fabricating the same are disclosed. The cutting tool having metallic glass thin film coated thereon comprises: a cutting element having a sharpened portion, and the cutting element is made of metal; and a metallic glass thin film coated on the cutting element, and the metallic glass is represented by the following formula 1 or formula 2, (Zr a Cu b Ni c Al d ) 100-x Si x ,  [formula 1] wherein 45=<a=<75, 25=<b=<35, 5=<c=<15, 5=<d=<15, 0.1=<x=<10, (Zr e Cu f Ag g Al h ) 100-y Si y ,  [formula 2] 35=<e=<55, 35=<f=<55, 5=<g=<15, 5=<h=<15, 0.1=<y=<10. The metallic glass cutting tool of the present invention comprises: a cutting element having a sharpened portion, and the cutting element is made of a metallic glass represented by the above formula 1 or formula 2.

What is claimed is: 
     
         1 . A method of forming a metallic glass thin film (MGTF) on a cutting element, which comprises steps:
 (A) providing a metallic glass target, and a composition of the metallic glass target is represented by a following formula 1 or formula 2; and   (B) sputtering to form the metallic glass thin film on a surface of the cutting element by using the metallic glass target as a cathode;
   (Zr a Cu b Ni c Al d ) 100-x Si x ,  [formula 1]
 
   wherein 45=<a=<75, 25=<b=<35, 5=<c=<15, 5=<d=<15, 0.1=<x=<10,
   (Zr e Cu f Ag g Al h ) 100-y Si y ,  [formula 2]
 
   35=<e=<55, 35=<f=<55, 5=<g=<15, 5=<h=<15, 0.1=<y=<10.   
     
     
         2 . The method of forming an MGTF on a cutting element as claimed in  claim 1 , wherein the metallic glass target is provided by the following steps:
 (A1) melting and mixing raw materials in a composition according to the formula 1 or the formula 2 and forming an ingot from the mixture;   (A2) vacuum suction casting the ingot and cooling to form a sheet; and   (A3) reprocessing the sheet to form the metallic glass target.   
     
     
         3 . The method of forming an MGTF on a cutting element as claimed in  claim 2 , wherein the cooling in the step (A2) is rapid cooling. 
     
     
         4 . The method of forming an MGTF on a cutting element as claimed in  claim 1 , wherein the method is used to improve a blade sharpness index (BSI) of the cutting element. 
     
     
         5 . The method of forming an MGTF on a cutting element as claimed in  claim 1 , wherein in the step (B), the thickness of the metallic glass thin film is 100 nm to 500 nm. 
     
     
         6 . The method of forming an MGTF on a cutting element as claimed in  claim 1 , wherein in the step (B), the sputtering is performed with a gas pressure of 1×10 −4  Pa to 1×10 −2  Pa. 
     
     
         7 . The method of forming an MGTF on a cutting element as claimed in  claim 1 , wherein in the step (B), the sputtering is performed in an inert gas or nitrogen gas atmosphere. 
     
     
         8 . A method of providing a metallic glass cutting tool, which comprises:
 (A) melting and mixing raw materials in a composition according to the formula 1 or the formula 2 and forming an ingot from the mixture;   (B) vacuum suction casting the ingot and rapid cooling to form a metallic glass sheet; and   (C) reprocessing the metallic glass sheet to provide a cutting element having a sharpened portion,
   (Zr a Cu b Ni c Al d ) 100-x Si x ,  [formula 1]
 
   wherein 45=<a=<75, 25=<b=<35, 5=<c=<15, 5=<d=<15, 0.1=<x=<10,
   (Zr e Cu f Ag g Al h ) 100-y Si y ,  [formula 2]
 
   35=<e=<55, 35=<f=<55, 5=<g=<15, 5=<h=<15, 0.1=<y=<10.   
     
     
         9 . The method of providing a metallic glass cutting tool as claimed in  claim 8 , wherein in the step (C), the metallic glass sheet is reprocessed by cutting to provide the cutting element.