Metal-and-resin composite and method for making the same

Abstract

A metal-and-resin composite includes an aluminum or aluminum alloy substrate, an aluminum oxide film on the aluminum or aluminum alloy substrate, and at least one resin article coupled to the aluminum oxide film. The aluminum or aluminum alloy substrate defines a plurality of corrosion pores, and the aluminum oxide film defines a plurality of nano-pores. Some of the nano-pores extend through the aluminum oxide film and couple to the corrosion pores. Some parts of the resin article fill in the nano-pores and the corrosion pores, thus greatly improving bond between the resin article and the aluminum or aluminum alloy substrate.

1 . A metal-and-resin composite comprising:
 an aluminum or aluminum alloy substrate defining a plurality of corrosion pores;   an aluminum oxide film on the aluminum or aluminum alloy substrate, and defining a plurality of nano-pores, some of the plurality of nano-pores extending through the aluminum oxide film and coupling to the corrosion pores; and   at least one resin article coupled to the aluminum oxide film.   
     
     
         2 . The metal-and-resin composite as claimed in  claim 1 , wherein some parts of the resin article fill in the nano-pores and the corrosion pores coupling to the nano-pores. 
     
     
         3 . The metal-and-resin composite as claimed in  claim 1 , wherein the nano-pores have an average diameter of about 10 nm to about 80 nm. 
     
     
         4 . The metal-and-resin composite as claimed in  claim 1 , wherein the aluminum oxide film has a thickness of less than 1 μm. 
     
     
         5 . The metal-and-resin composite as claimed in  claim 4 , wherein the aluminum oxide film has a thickness of about 500 nm. 
     
     
         6 . The metal-and-resin composite as claimed in  claim 1 , wherein the resin article is made of resin selected from a group consisting of polyphenylene sulfide, polyamide, polybutylene terephthalate, polyethylene terephthalate, thermoplastic polyurethane elastomer, thermoplastic polyester elastomer, polycarbonate, or any combination thereof. 
     
     
         7 . The metal-and-resin composite as claimed in  claim 1 , wherein the resin article is made of resin containing glass fiber, the resin is selected from a group consisting of polyphenylene sulfide, polyamide, polybutylene terephthalate, polyethylene terephthalate, polycarbonate, or any combination thereof. 
     
     
         8 . The metal-and-resin composite as claimed in  claim 7 , wherein when the resin is polyphenylene sulfide, polybutylene terephthalate, polyethylene terephthalate, or polycarbonate, the resin article comprises about 30 wt % glass fiber; when the resin is polyamide, the resin article comprises about 50 wt % glass fiber. 
     
     
         9 . A method for making a metal-and-resin composite, comprising:
 providing an aluminum or aluminum alloy article;   electrochemically treating the aluminum or aluminum alloy article to form an aluminum or aluminum alloy substrate defining corrosion pores and an aluminum oxide film on the aluminum or aluminum alloy substrate, the aluminum oxide film defining nano-pores, some nano-pores extending through the aluminum oxide film and coupling to the corrosion pores; and   inserting the aluminum or aluminum alloy substrate together with the aluminum oxide film in a mold and molding resin on the surface of the aluminum oxide film to form at least one resin article.   
     
     
         10 . The method as claimed in  claim 9 , wherein the nano-pores have an average diameter of about 10 to about 80 nm; and the aluminum oxide film has a thickness of less than 1 μm. 
     
     
         11 . The method as claimed in  claim 9 , wherein some parts of the resin article fill in the nano-pores and the corrosion pores coupling to the nano-pores. 
     
     
         12 . The method as claimed in  claim 9 , wherein the electrochemically treating is carried out in an acid water solution having a temperature of about 10 to about 30° C. for about 3 to about 15 minutes, the aluminum or aluminum alloy article is an anode; the acid water solution comprises phosphoric acid having a concentration of about 100 to about 250 ml/L, sulfuric acid having a concentration of about 20 to about 60 ml/L, oxalic acid having a concentration of about 1 to about 10 ml/L, and citric acid having a concentration of about 0.5 to about 2.5 ml/L; the electric current density through the acid solution is about 0.5 to about 4 A/dm 2 . 
     
     
         13 . The method as claimed in  claim 9 , further comprising a step of etching the aluminum or aluminum alloy article using an alkaline water solution before electrochemically treating the aluminum or aluminum alloy article. 
     
     
         14 . The method as claimed in  claim 13 , wherein the etching step is carried out by dipping the aluminum or aluminum alloy article in a sodium hydroxide water solution having a concentration of about 30% to about 60% by weight for about 1 to about 3 minutes. 
     
     
         15 . The method as claimed in  claim 13 , further comprising a step of degreasing the aluminum or aluminum alloy article using a sodium salt water solution before etching the aluminum or aluminum alloy article. 
     
     
         16 . The method as claimed in  claim 15 , wherein the degreasing step is carried out by dipping the aluminum or aluminum alloy article in a sodium hydroxide water solution for about 5 to about 15 minutes, the sodium salt water solution comprises sodium carbonate having a concentration of about 30 to about 50 g/L, sodium phosphate having a concentration of about 30 to about 50 g/L, and sodium silicate having a concentration of about 3 to about 5 g/L. 
     
     
         17 . The method as claimed in  claim 9 , wherein the resin article is made of resin selected from a group consisting of polyphenylene sulfide, polyamide, polybutylene terephthalate, polyethylene terephthalate, thermoplastic polyurethane elastomer, thermoplastic polyester elastomer, polycarbonate, or any combination thereof. 
     
     
         18 . The method as claimed in  claim 9 , wherein the resin article is made of resin containing glass fiber, the resin is one selected from a group consisting of polyphenylene sulfide, polyamide, polybutylene terephthalate, polyethylene terephthalate, or polycarbonate. 
     
     
         19 . The method as claimed in  claim 18 , wherein when the resin is polyphenylene sulfide, polybutylene terephthalate, polyethylene terephthalate, or polycarbonate, the resin article comprises about 30 wt % glass fiber; when the resin is polyamide, the resin article comprises about 50 wt % glass fiber. 
     
     
         20 . A method for making a metal-and-resin composite, comprising:
 providing an aluminum or aluminum alloy article;   electrochemically treating the aluminum or aluminum alloy article to form an aluminum or aluminum alloy substrate defining corrosion pores and an aluminum oxide film on the aluminum or aluminum alloy substrate, the electrochemically treating being carried out in an acid water solution, the acid water solution comprising phosphoric acid having a concentration of about 100 to about 250 ml/L, sulfuric acid having a concentration of about 20 to about 60 ml/L, oxalic acid having a concentration of about 1 to about 10 ml/L, and citric acid having a concentration of about 0.5 to about 2.5 ml/L, the aluminum oxide film having a thickness of less than 1 μm, the aluminum oxide film defining nano-pores, some nano-pores extending through the aluminum oxide film and coupling to the corrosion pores; and   inserting the aluminum or aluminum alloy substrate together with the aluminum oxide film in a mold and molding resin on the surface of the aluminum oxide film to form at least one resin article.