Composite and method for making same

Abstract

A composite toughened against chipping during machining and other operations includes a substrate and a coating layer includes a substrate and a coating layer. The substrate is titanium or titanium alloys. Nano-holes are formed on a surface of the substrate. The coating layer completely fills in the nano-holes and completely covers the surface of the substrate where the nano-holes are not formed. The disclosure further provides a method for making such composite.

What is claimed is: 
     
         1 . A composite comprising:
 a substrate, wherein a material of the substrate being selected from one of titanium and titanium alloys;   nano-holes formed on a surface of the substrate; and   a coating layer covers the surface of the substrate, and the nano-holes are filled with the coating layer.   
     
     
         2 . The composite of  claim 1 , wherein the nano-holes are irregular cavities, diameters of the nano-hole vary in a range from several tens of nanometers to several hundreds of nanometers. 
     
     
         3 . The composite of  claim 1 , wherein the shape of the nano-holes are similar to honeycomb structure. 
     
     
         4 . The composite of  claim 1 , wherein protrusions accompany the nano-holes, the protrusions are formed beside the nano-holes. 
     
     
         5 . The composite of  claim 1 , wherein protrusions accompany the nano-holes, the protrusions are formed in the nano-holes. 
     
     
         6 . The composite of  claim 1 , wherein the titanium alloys can be selected from a group consisting of TAD, TA 0 , TA 1 , TA 2 , TA 3 , TA 4 , TA 5 , TA 6 , TA 7 , TA 9 , TA 10 , TB 2 , TB 3 , TB 4 , TC 1 , TC 2 , TC 3 , TC 4 , TC 6 , TC 9 , TC 10 , TC 11  and TC 12 . 
     
     
         7 . The composite of  claim 1 , wherein the coating layer is a nanometric ceramic coating layer. 
     
     
         8 . A method for making a composite comprising:
 providing a substrate, wherein the material of the substrate being selected from one of titanium and titanium alloys;   forming nano-holes on a surface of the substrate by surface treatment;   forming a coating layer on the surface of the substrate having the nano-holes, the coating layer covers the surface of the substrate, and the nano-holes are filled with the coating layer.   
     
     
         9 . The method of  claim 8 , wherein the surface treatment comprises treating the substrate with a pickling solution, the pickling solution comprises 1-8% by weight of organic acid, 1-15% by weight of inorganic acid, 0.1-3% by weight of additive, 0.5-4% by weight of hydrogen peroxide, and 83-97% by weight of pure water. 
     
     
         10 . The method of  claim 9 , wherein the organic acid is one or more of acetic acid, formic acid and oxalic acid, the inorganic acid is one or more of hydrofluoric acid, sulfamic acid, and nitric acid, the additive is one or more of potassium fluoride, sodium fluoride, magnesium fluoride, and copper sulfate. 
     
     
         11 . The method of  claim 8 , wherein the nano-holes are irregular cavities, diameters of the nano-holes vary in a range from several tens of nanometers to several hundreds of nanometers. 
     
     
         12 . The method of  claim 8 , wherein the shape of the nano-holes are similar to honeycomb structure. 
     
     
         13 . The method of  claim 8 , wherein protrusions accompany the nano-holes, the protrusions are formed beside the nano-holes. 
     
     
         14 . The method of  claim 8 , wherein protrusions accompany the nano-holes, the protrusions are formed in the nano-holes. 
     
     
         15 . The method of  claim 8 , wherein the titanium alloys can be selected from a group consisting of TAD, TA 0 , TA 1 , TA 2 , TA 3 , TA 4 , TA 5 , TA 6 , TA 7 , TA 9 , TA 10 , TB 2 , TB 3 , TB 4 , TC 1 , TC 2 , TC 3 , TC 4 , TC 6 , TC 9 , TC 10 , TC 11  and TC 12 . 
     
     
         16 . The method of  claim 8 , wherein the coating layer is a nanometric ceramic coating layer.