Method of coating hub and electroplating a portion thereof

Abstract

A process of manufacturing a wheel hub comprises coating a blank made of aluminum alloy on a surface of the blank, removing a portion of the blank for exposing the aluminum alloy of the blank to be electroplated, polishing the exposed portion of the blank, removing wax and oil stains from the surface of the blank, sequentially electroplating nickel and copper on the exposed portion of the blank, polishing the copper layer on the exposed portion of the blank, removing wax and oil stains from the surface of the blank, sequentially electroplating a plurality of nickel layers having different concentrations of sulfur on the copper layer, and electroplating chrome on the nickel layers for producing the wheel hub.

1 . A process of manufacturing a wheel hub, comprising the steps of: 
 (a) coating a blank made of aluminum alloy on a surface of the blank;    (b) removing a portion of the blank for exposing the aluminum alloy of the blank to be electroplated;    (c) polishing the exposed portion of the blank;    (d) removing wax and oil stains from the surface of the blank;    (e) sequentially electroplating nickel and copper on the exposed portion of the blank;    (f) polishing the copper layer on the exposed portion of the blank;    (g) removing wax and oil stains from the surface of the blank;    (h) sequentially electroplating a plurality of nickel layers having different concentrations of sulfur on the copper layer; and    (i) electroplating chrome on the nickel layers for producing the wheel hub.    
   
   
       2 . The process of  claim 1 , wherein the step (c) comprises the sub-step of polishing corners or grooves on the exposed portion of the blank; the step (d) comprises the sub-steps of submerging the blank in a first solution, removing wax deposited on the surface of the blank, cleaning the blank with water, submerging the blank in a second solution, and cleaning the blank with water; the step (e) comprises the sub-steps of submerging the blank in a third solution having a weak acid for etching out an oxidized layer on the exposed portion of the blank, cleaning the blank with water, removing Al 2 O 3  from the exposed portion of the blank by a solution prepared by mixing nitric acid, sulfuric acid, phosphotvaa2d, and detergent, cleaning the blank with water, depositing a layer of zinc on the exposed portion of the blank by submerging the blank in a fourth solution, removing zinc and Al 2 O 3  from the exposed portion of the blank by submerging in a fifth solution, cleaning the blank with water, depositing a layer of zinc on the exposed portion of the blank, cleaning the blank with water, electroplating liquid nickel on the exposed portion of the blank, cleaning the blank with water, activating the exposed portion of the blank in a first predetermined acid solution, cleaning the blank with water, electroplating copper on the exposed portion of the blank, cleaning the blank with water, passivating the exposed portion of the blank coated with copper in a second predetermined acid solution, and cleaning the blank with water; the step (f) comprises the sub-steps of spraying copper on the corners or the grooves on the exposed portion of the blank, smoothing the same, and polishing the same; the step (g) comprises the sub-steps of submerging the blank in sixth solution for removing copper, cleaning the blank with water, submerging the blank in a seventh solution for removing oil stains from the exposed portion of the blank, cleaning the blank with water, neutralizing acid substance on the copper layer of the exposed portion of the blank, cleaning the blank with water, depositing a zinc layer on the exposed portion of the blank, and cleaning the blank with water; the step (h) comprises the sub-steps of removing oil stains from the exposed portion of the blank by electrolysis, cleaning the blank with water, activating the copper layer of the blank in a third predetermined acid solution, cleaning the blank with water, electroplating liquid nickel of low brightness on the exposed portion of the blank, electroplating liquid nickel having a high concentration of sulfur on the exposed portion of the blank, electroplating liquid nickel of high brightness on the exposed portion of the blank, electroplating liquid nickel of high concentration on the exposed portion of the blank, and cleaning the blank with water; and the step (i) comprises the sub-steps of installing an anode, electrolyzing the blank, cleaning the blank with water, activating the nickel layer on the exposed portion of the blank by means of chromic acid, electroplating a layer of chrome on the exposed portion of the blank, cleaning the blank with water, reducing Cl 6  ions in the electrolyte as Cl 3  ions by adding NaHSO 3  therein, cleaning the blank with water, removing the anode, and cleaning the blank with water.  
   
   
       3 . The process of  claim 1 , further comprising the step (i) of packing the produced wheel hub.  
   
   
       4 . The process of  claim 2 , wherein the (i) step further comprises the sub-step of packing the produced wheel hub.  
   
   
       5 . The process of  claim 2 , wherein the liquid nickel is adapted to feed back.  
   
   
       6 . The process of  claim 2 , wherein the chromic acid is adapted to feed back.