Method for forming coating film having high heat resistance, high hardness and abrasion resistance, coating film having high heat resistance, high hardness and abrasion resistance, and cutting tool comprising same
The present disclosure relates to a method for producing a coating film having high heat resistance, high hardness and wear resistance, a coating film having high heat-resistance, high hardness and wear resistance produced using the method, and a cutting tool including the same. The method includes forming a metal nitride layer on a metal base; forming a carbon layer on the metal nitride layer; and irradiating a laser into the carbon layer to add carbons into a portion of the metal nitride layer, thereby to form a carburized layer.
1. A method for producing a coating film having high heat resistance, high hardness and wear resistance, the method comprising:
forming a metal nitride layer on a metal base;
forming a dried carbon layer on the metal nitride layer; and
irradiating a laser into the dried carbon layer to add carbons into a portion of the metal nitride layer, thereby to form a carburized layer,
wherein the metal nitride layer includes titanium (Ti) and at least one of zirconium (Zr) and chromium (Cr), and
wherein the carburized layer includes a compound in which carbon is added in a substitutional manner, into the metal nitride to form a compound expressed as Ti 1-x M x (C y N 1-y ) (0<x<1, 0<y<1), wherein M is Zr or Cr.
2. The method of claim 1 , wherein forming the carburized layer includes irradiating a pulse or continuous wave laser into the carbon layer.
3. The method of claim 1 , wherein the carburized layer includes titanium carbide (TiC).
4. The method of claim 1 , wherein the carburized layer includes:
a high carbon content portion; and
a low carbon content portion disposed between a portion of the metal nitride layer remaining after the carburization and the high carbon content portion, wherein the low carbon content portion has a smaller carbon content per unit area than a carbon content per unit area of the high carbon content portion.
5. The method of claim 4 , wherein the high carbon content portion comprises titanium carbide (TiC).
6. The method of claim 1 , wherein the method further comprises removing a portion of the carbon layer remaining after forming the carburized layer.
7. The method of claim 1 , wherein the carbon layer is made of graphite or carbon nanotube (CNT).
8. The method of claim 1 , wherein forming the carbon layer includes coating a carbon paste containing a carbon material, a binder and a solvent on the metal nitride layer.
9. The method of claim 8 , wherein when the carbon material is graphite, a size of graphite is 1 nm or larger, and is 20 μm or smaller.
10. The method of claim 1 , wherein the method further includes forming a titanium layer on the metal base prior to forming the metal nitride layer,
wherein in forming the metal nitride layer, the titanium layer is nitrided to form an adhesion improving layer made of titanium nitride (TiN).