Alloy for use in a sacrificial anode and a sacrificial anode

Abstract

The present invention relates to an aluminum-based alloy for use in a sacrificial anode and a sacrificial anode produced from the aluminum-based alloy suitable for use in colder waters. The aluminum-based alloy comprises: minimum 0.01% by weight of silicon maximum 0.003% by weight of copper, maximum 0.04% by weight of indium, maximum 0.08% by weight of iron, maximum 0.8% by weight of zinc, elements in form of impurities in an amount of maximum 0.1% by weight, and balance aluminum. The alloy has a high electrochemical efficiency and a low potential and providing good properties in respect of cathodic protection on water temperatures below 10 degrees celcius.

1 . An aluminum-based alloy for use in a sacrificial anode, characterized in that it comprises:
 minimum 0.01% by weight of silicon   maximum 0.003% by weight of copper,   maximum 0.04% by weight of indium,   maximum 0.08% by weight of iron,   maximum 0.8% by weight of zinc,   elements in form of impurities in an amount of maximum 0.1% by weight, and balance aluminum.   
     
     
         2 . An aluminum-based alloy according to  claim 1 , characterized in that it comprises:
 minimum 0.01% by weight of silicon   between 0.0005-0.003% by weight of copper,   between 0.01-0.04% by weight of indium,   between 0.01-0.08% by weight of iron,   between 0.01-0.8% by weight of zinc,   elements in form of impurities in an amount of maximum 0.1% by weight, and balance aluminum.   
     
     
         3 . An aluminum-based alloy according to  claim 1 , characterized in that it comprises:
 between 0.01-0.12% by weight of silicon,   between 0.0005-0.003% by weight of copper,   between 0.01-0.04% by weight of indium,   between 0.01-0.08% by weight of iron,   between 0.01-0.8% by weight of zinc,   elements in form of impurities in an amount of maximum 0.1% by weight, and balance aluminum.   
     
     
         4 . The aluminum-based alloy according to  claim 3  comprising:
 between 0.01-0.12% by weight of silicon, 
 between 0.0005-0.003% by weight of copper, 
 between 0.01-0.04% by weight of indium, 
 between 0.01-0.08% by weight of iron, 
 between 0.01-0.5% by weight of zinc, 
 elements in form of impurities in an amount of maximum 0.1% by weight of each element, and 
 balance aluminum. 
 
     
     
         5 . The aluminum-based alloy according to  claim 1 , wherein the aluminum has a purity of at least 99.0% by weight. 
     
     
         6 . The aluminum-based alloy according to  claim 1 , wherein the aluminum has a purity of at least 99.5% by weight. 
     
     
         7 . The aluminum-based alloy according to  claim 1 , wherein the aluminum has a purity in the ranges 99.90 to 99.99% by weight. 
     
     
         8 . The aluminum-based alloy according to  claim 1 , wherein the aluminum-based alloy has an electrochemical efficiency above 1500 Ah/kg, preferably above 2000 Ah/kg, such as above 2500 Ah/kg, when tested according to DvN RP B401. 
     
     
         9 . The use of an aluminum-based alloy according to  claim 1 , in a sacrificial anode for protecting metallic constructions in a humid and marine environment. 
     
     
         10 . A sacrificial anode for protecting metallic constructions in a humid and marine environment, said sacrificial anode comprises an aluminum-based alloy according to  claim 1 .