Method of laser treating an alumina surface

Abstract

The method of laser treating an alumina surface includes applying a coating of a phenolic resin including particles of titanium carbide (TiC) and boron carbide (B 4 C) to an alumina (Al 2 O 3 ) surface to form a resin-coated alumina surface, heating the resin-coated alumina surface to form a carbon-coated alumina surface, and scanning the carbon-coated alumina surface a nitrogen gas-assisted CO 2 laser beam to form a laser-treated surface. The particles of titanium carbide (TiC) and boron carbide (B 4 C) each have a diameter of about 350 nm.

We claim: 
     
         1 . A method of laser treating an alumina surface, comprising the steps of:
 providing a phenolic resin and hard particle mixture, the phenolic resin and hard particle mixture including a phenolic resin and a mixture of at least two chemically different hard particles;   applying the phenolic resin and hard particle mixture to the alumina (Al 2 O 3 ) surface to form a resin-coated alumina surface;   heating the resin-coated alumina surface to form a carbon-coated alumina surface, the carbon-coated alumina surface including a carbon film; and   scanning the carbon-coated alumina surface with a nitrogen gas-assisted CO 2  laser beam to provide a laser-treated surface, the laser-treated surface including AlN and/or AlON.   
     
     
         2 . The method of laser treating an alumina surface as recited in  claim 1 , wherein the at least two chemically different hard particles include titanium carbide (TiC) and boron carbide (B 4 C). 
     
     
         3 . The method of laser treating an alumina surface as recited in  claim 1 , wherein the hard particle mixture includes titanium carbide (TiC) and boron carbide (B 4 C) in a ratio of about 3 wt % of TiC and 3 wt % of B 4 C. 
     
     
         4 . The method of laser treating an alumina surface as recited in  claim 1 , wherein the carbon film has a thickness of about 40 μm. 
     
     
         5 . The method of laser treating an alumina surface as recited in  claim 4 , wherein the step of heating the resin-coated alumina surface comprises heating the resin-coated alumina surface at a temperature of about 175° C. and a pressure of about 8 bar. 
     
     
         6 . The method of laser treating an alumina surface as recited in  claim 5 , wherein the step of heating the resin-coated alumina surface further comprises heating the resin-coated alumina surface at a temperature of about 400° C. in an inert gas atmosphere. 
     
     
         7 . A method of laser treating an alumina surface, comprising the steps of:
 applying a coating of a phenolic resin and hard particle mixture to an alumina (Al 2 O 3 ) surface to provide a resin-coated alumina surface, the phenolic resin and hard particle mixture including a phenolic resin, titanium carbide (TiC), and boron carbide (B 4 C);   heating the resin-coated alumina surface to form a carbon-coated alumina surface, the carbon-coated alumina surface including a carbon film having a thickness of about 40 μm; and   scanning the carbon-coated alumina surface with an inert gas-assisted CO 2  laser beam to provide a laser-treated surface.   
     
     
         8 . The method of laser treating an alumina surface as recited in  claim 7 , wherein particles of titanium carbide (TiC) and boron carbide (B 4 C) in the phenolic resin and hard particle mixture each have a diameter of about 350 nm. 
     
     
         9 . The method of laser treating an alumina surface as recited in  claim 7 , wherein the titanium carbide (TiC) and the boron carbide (B 4 C) are present in a ratio of about 3 wt % of TiC and 3 wt % of B 4 C. 
     
     
         10 . The method of laser treating an alumina surface as recited in  claim 7 , wherein the step of heating the resin-coated alumina surface comprises heating the coated alumina surface at a temperature of about 175° C. and a pressure of about 8 bar. 
     
     
         11 . The method of laser treating an alumina surface as recited in  claim 10 , wherein the step of heating the resin-coated alumina surface further comprises heating the resin-coated alumina surface at a temperature of about 400° C. in an inert gas atmosphere. 
     
     
         12 . A method of laser treating an alumina surface, comprising the steps of:
 applying a phenolic resin and hard particle mixture to an alumina (Al 2 O 3 ) surface to provide a resin-coated alumina surface, the phenolic resin and hard particle mixture including a phenolic resin, titanium carbide (TiC), and boron carbide (B 4 C), the titanium carbide (TiC) and the boron carbide (B 4 C) being present in a ratio of about 3 wt % of TiC and 3 wt % of B 4 C;   heating the resin-coated alumina surface to form a carbon-coated alumina surface; and   scanning the carbon-coated alumina surface with an inert gas-assisted CO 2  laser beam to provide a laser-treated surface.   
     
     
         13 . The method of laser treating an alumina surface as recited in  claim 12 , wherein particles of titanium carbide (TiC) and boron carbide (B 4 C) in the phenolic resin and hard particle mixture each have a diameter of about 350 nm. 
     
     
         14 . The method of laser treating an alumina surface as recited in  claim 12 , wherein the step of heating the resin-coated alumina surface comprises heating the resin coated alumina surface at a temperature of about 175° C. and a pressure of about 8 bar. 
     
     
         15 . The method of laser treating an alumina surface as recited in  claim 14 , wherein the step of heating the resin-coated alumina surface further comprises heating the resin coated alumina surface at a temperature of about 400° C. in an inert gas atmosphere.