Aluminum alloy-and-resin composite and method for making the same

Abstract

An aluminum alloy-and-resin composite includes an aluminum alloy substrate, an anodic oxide film formed on the substrate, and resin composition bonded with the anodic oxide film. The anodic oxide film has nano-pores with an average diameter of about 30-60 nm. The resin composition fills the nano-pores and coatings surfaces of the anodic oxide film. The resin composition contains crystalline thermoplastic synthetic resins.

1 . An aluminum alloy-and-resin composite, comprising:
 an aluminum alloy substrate with an anodic oxide film having nano-pores with an average diameter of about 30-60 nm on its surface; and   resin composition integrally bonded to the surface of the aluminum alloy substrate having the anodic oxide film, the resin composition filling the nano-pores of the anodic oxide film, the resin composition containing crystalline thermoplastic synthetic resins.   
     
     
         2 . The composite as claimed in  claim 1 , wherein the resin composition is formed by molding crystalline thermoplastic synthetic resin on the anodic oxide film. 
     
     
         3 . The composite as claimed in  claim 1 , wherein the crystalline thermoplastic synthetic resin is polyphenylene sulfide, polyamide, polyethylene terephthalate, or polybutylene terephthalate. 
     
     
         4 . The composite as claimed in  claim 3 , wherein the crystalline thermoplastic synthetic resin is polyphenylene sulfide added with fiberglass, the fiberglass has a mass percentage of about 10-50%. 
     
     
         5 . A method for making an aluminum alloy-and-resin composite, comprising:
 providing an aluminum alloy substrate;   roughening the surface of the substrate;   anodizing the substrate to form an anodic oxide film on the substrate, the anodic oxide film defining nano-pores having an average diameter of about 30-60 nm;   positioning the anodized substrate in a mold and molding crystalline thermoplastic synthetic resin on the anodic oxide film and filling the nano-pores of the anodic oxide film to form the composite.   
     
     
         6 . The method as claimed in  claim 5 , wherein roughening the substrate includes the step of dipping the substrate in an alkaline solution having a temperature of about 40-55° C. for about 1-2 minutes. 
     
     
         7 . The method as claimed in  claim 6 , wherein the alkaline solution includes sodium hydroxide having a concentration of about 20-35 g/L, and sodium carbonate having a concentration of about 20-30 g/L. 
     
     
         8 . The method as claimed in  claim 5 , wherein anodizing the substrate is carried out in a sulfuric acid solution for about 15-60 minutes, the concentration of the sulfuric acid is about 100-250 ml/L, the electric current density through the sulfuric acid solution is about 0.5-4.9 A/dm 2 . 
     
     
         9 . The method as claimed in  claim 5 , wherein anodizing the substrate is carried out in a phosphoric acid solution or an oxalic acid solution. 
     
     
         10 . The method as claimed in  claim 5 , wherein the crystalline thermoresin is polyphenylene sulfide, polyamide, polyethylene terephthalate, or polybutylene terephthalate. 
     
     
         11 . The method as claimed in  claim 10 , wherein the crystalline thermoplastic synthetic resin is polyphenylene sulfide added with fiberglass, the fiberglass has a mass percentage of about 10-50%. 
     
     
         12 . The method as claimed in  claim 5 , further comprising a step of degreasing the substrate before roughening the substrate. 
     
     
         13 . The method as claimed in  claim 12 , wherein degreasing the substrate comprises dipping the substrate in a sodium salt solution. 
     
     
         14 . The method as claimed in  claim 13 , wherein the sodium salt solution includes sodium carbonate having a concentration of about 30-50 g/L, sodium phosphate having a concentration of about 30-50 g/L, and sodium silicate having a concentration of about 3-5 g/L. 
     
     
         15 . An aluminum alloy-and-resin composite, comprising:
 an aluminum alloy substrate;   an anodic oxide film having nano-pores with an average diameter of about 30-60 nm formed on a surface of the substrate, and   resin composition integrally molded on the surface of the aluminum alloy substrate having the anodic oxide film, the resin composition filling the nano-pores of the anodic oxide film, the resin composition containing crystalline thermoplastic synthetic resins.   
     
     
         16 . The composite as claimed in  claim 15 , wherein the anodic oxide film and the nano-pores are formed by roughing and anodizing the substrate. 
     
     
         17 . The composite as claimed in  claim 16 , wherein roughing the substrate comprising the step of chemically etching the substrate. 
     
     
         18 . The composite as claimed in  claim 17 , wherein chemically etching the substrate includes the step of dipping the substrate in an alkaline solution having a temperature of about 40-55° C. for about 1-2 minutes. 
     
     
         19 . The composite as claimed in  claim 18 , wherein the alkaline solution includes sodium hydroxide having a concentration of about 20-35 g/L, and sodium carbonate having a concentration of about 20-30 g/L. 
     
     
         20 . The composite as claimed in  claim 15 , wherein the crystalline thermoplastic synthetic resin is polyphenylene sulfide, polyamide, polyethylene terephthalate, or polybutylene terephthalate.