Aluminum films having hardening particles

Abstract

The described embodiments relate generally to aluminum layer and methods for forming aluminum layer onto metal substrates. Methods involve increasing the hardness of the aluminum layers by embedding hardening particles therein. According to some embodiments, hardening particles are co-deposited with aluminum onto a substrate using an electroplating process. The electrolytic process involves using an electrolytic bath having the hardening particles dispersed therein. The hardening particles can form a supportive network within the aluminum layer that increases the hardness of the aluminum layer. In some embodiments, a portion of the aluminum layer is converted to aluminum oxide.

1 . A method for forming a hardened aluminum layer on a substrate, the method comprising:
 exposing at least a portion of a surface of the substrate to a mixture of aluminum ions and hardening particles, the hardening particles characterized as having an average particle size larger than an average particle size of the aluminum ions;   creating a flow of aluminum ions by causing at least a portion of the aluminum ions to move toward the substrate surface upon applying an electric field to the mixture; and   creating a flow of hardening particles by causing at least some of the hardening particles to flow toward the substrate surface in accordance with the flow of aluminum ions, wherein at least a fraction of the aluminum ions from the flow of aluminum ions and at least a fraction of the hardening particles from the flow of hardening particles aggregate on the substrate surface forming an aggregate of aluminum metal and hardening particles on the substrate surface, the aggregate having a hardness value greater than that of aluminum metal.   
     
     
         2 . (canceled) 
     
     
         3 . The method of  claim 1 , wherein the mixture of hardening particles and aluminum ions comprise an electrolytic bath. 
     
     
         4 . The method of  claim 3 , further comprising:
 agitating the hardening particles within the electrolytic bath.   
     
     
         5 . The method of  claim 4 , wherein agitating the hardening particles includes bubbling gas within the electrolytic bath that forces movement of the hardening particles within the electrolytic bath. 
     
     
         6 . The method of  claim 4 , wherein agitating the hardening particles includes circulating the electrolytic bath causing movement of the hardening particles within the electrolytic bath. 
     
     
         7 . The method of  claim 3 , wherein a least some of the hardening particles have coatings that cause the coated hardening particles to repel each other and cause the coated hardening particles to be suspended within the electrolytic bath. 
     
     
         8 . The method of  claim 4 , wherein a least some of the hardening particles have coatings that cause the coated hardening particles to repel each other and cause the coated hardening particles to be suspended within the electrolytic bath. 
     
     
         9 . The method of  claim 1 , wherein the hardening particles comprise nitride particles and/or carbide particles. 
     
     
         10 . The method of  claim 1  further comprising converting at least part of the second portion to an aluminum oxide layer, and wherein the hardening particles comprise nitride particles and/or carbide particles. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . The method of  claim 9 , wherein the hardening particles within the aggregate are characterized as having an average particle width of less than about one-third of a thickness of the aggregate. 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . (canceled) 
     
     
         20 . The method of  claim 1 , further comprising:
 converting at least a portion of the aggregate to an aluminum oxide layer comprising anodic pores using an anodizing process, wherein during the anodizing process the anodic pores form around the hardening particles such that the hardening particles are positioned within the aluminum oxide layer and outside of the pores.   
     
     
         21 . A part, comprising:
 a substrate;   a hardened aluminum layer disposed on the substrate, the hardened aluminum layer comprising:
 aluminum metal; and 
 a supportive network having hardening particles substantially uniformly dispersed within the aluminum metal, the supportive network adding a hardening quality to the aluminum metal such that the hardened aluminum layer is more resistant to denting compared to an aluminum metal layer without the supportive network. 
   
     
     
         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . The part of  claim 21 , wherein the hardening particles are characterized as an average particle width of less than about one-third of a thickness of the hardened aluminum layer. 
     
     
         27 . The part of  claim 21 , wherein the hardening particles are characterized as having an average particle width of less than about one-third of a thickness of the hardened aluminum layer. 
     
     
         28 . The part of  claim 21 , wherein the hardened aluminum layer includes a first portion of hardening particles, the part further comprising:
 an aluminum oxide layer disposed on the hardened aluminum layer, the aluminum oxide layer having anodic pores and having a second portion of hardening particles, wherein the second portion of hardening particles are positioned outside of the anodic pores.   
     
     
         29 . A method for plating aluminum on a substrate surface, comprising:
 exposing the surface of the substrate to an aluminum electrolytic bath comprising hardening particles dispersed therein; and   causing aluminum to deposit onto the substrate surface by applying an electric field to the electrolytic bath, wherein at least a fraction of the hardening particles are co-deposited with the aluminum forming an aggregate layer on the substrate surface, the aggregate layer including a network of hardening particles substantially uniformly dispersed within the aluminum.   
     
     
         30 . The method of  claim 29 , wherein the aggregate layer has a hardness value greater than a hardness value of an aluminum layer without hardening particles. 
     
     
         31 . The method of  claim 29 , wherein the hardening particles comprises at least one of carbide particles and nitride particles. 
     
     
         32 . The method of  claim 30 , wherein the hardening particles comprises at least one of carbide particles and nitride particles. 
     
     
         33 . (canceled) 
     
     
         34 . (canceled) 
     
     
         35 . (canceled) 
     
     
         36 . The method of  claim 29 , wherein the hardening particles within the aggregate layer are characterized as having an average particle width of less than about one-third of a thickness of the aggregate layer.