Metal quenching medium

Abstract

Disclosed is a quenching medium for treating a heated metal part, said medium comprising water and a polyacrylate terpolymer comprising acrylamide and/or methacrylamide monomer units, acrylic acid and/or methacrylic acid monomer units and alkyl alkoxylate allyl ether monomer units where the acid groups are in the form of an alkali metal salt and where the alkyl alkoxylate allyl ether monomers are of the formula where n is an integer from 1 to about 30, R is ethylene, propylene or butylene and G is an alkyl group of 8 to 30 carbon atoms. Also disclosed is a method for quenching a heated metal part, which process comprises immersing said metal part in the quenching medium. Also disclosed are the polyacrylate ternary copolymers.

1 . A quenching medium for treating a heated metal part, said medium comprising 
 water and    a polyacrylate terpolymer comprising 
 acrylamide and/or methacrylamide monomer units,  
 acrylic acid and/or methacrylic acid monomer units  
 and  
 alkyl alkoxylate allyl ether monomer units  
 where the acid groups are in the form of an alkali metal salt and  
 where the alkyl alkoxylate allyl ether monomers are of the formula  
                     
 where n is an integer from 1 to about 30, R is ethylene, propylene or butylene and G is an alkyl group of 8 to 30 carbon atoms.  
   
     
     
         2 . A quenching medium according to  claim 1  where R is 1,2-ethylene or 1,2-propylene.  
     
     
         3 . A quenching medium according to  claim 1  where n is from about 10 to about 20 and G is an alkyl group of 12 to 24 carbon atoms.  
     
     
         4 . A quenching medium according to  claim 1  where the weight:weight ratio acrylamide and/or methacrylamide:acrylic acid and/or methacrylic acid monomer units is from about 4:1 to about 1:4.  
     
     
         5 . A quenching medium according to  claim 1  where the weight:weight ratio of acrylamide and/or methacrylamide:acrylic acid and/or methacrylic acid monomer units is from about 2:1 to about 3:1.  
     
     
         6 . A quenching medium according to  claim 1  where the alkyl alkoxylate allyl ether monomer units are up to about 10% by weight of the terpolymer.  
     
     
         7 . A quenching medium according to  claim 1  where the alkyl alkoxylate allyl ether monomer units are up to about 5% by weight of the terpolymer.  
     
     
         8 . A quenching medium according to  claim 1  where the terpolymer has a weight average molecular weight of between about 20,000 and about 80,000.  
     
     
         9 . A quenching medium according to  claim 1  where the terpolymer is between about 0.5% and about 15% of the medium by weight.  
     
     
         10 . A quenching medium according to  claim 1  further comprising a polymer selected from the group consisting of the (acrylamide and/or methacrylamide)/(acrylic acid and/or methacrylic acid) copolymers, poly(alkylene oxide) polymers, polyacrylates, polyvinylpyrrlidone and polyethyloxazoline.  
     
     
         11 . A process for quenching a heated metal part, which process comprises 
 preparing a quenching medium comprising 
 water and  
 a polyacrylate terpolymer comprising 
 acrylamide and/or methacrylamide monomer units,  
 acrylic acid and/or methacrylic acid monomer units  
 and  
 alkyl alkoxylate allyl ether monomer units,  
 where the acid groups are in the form of an alkali metal salt and  
 where the alkyl alkoxylate allyl ether monomers are of the formula  
                     
 where n is an integer from 1 to about 30, R is ethylene, propylene or butylene and G is an alkyl group of 8 to 30 carbon atoms and  
 
   immersing the heated metal part in the quenching medium for a period of time to accomplish the quenching.    
     
     
         12 . A polyacrylate terpolymer comprising 
 acrylamide and/or methacrylamide monomer units,    acrylic acid and/or methacrylic acid monomer units    and    alkyl alkoxylate allyl ether monomer units,    where the alkyl alkoxylate allyl ether monomers are of the formula                          where n is an integer from 1 to about 30, R is ethylene, propylene or butylene and G is an alkyl group of 8 to 30 carbon atoms.    
     
     
         13 . A terpolymer according to  claim 12  where R is 1,2-ethylene or 1,2-propylene.  
     
     
         14 . A terpolymer according to  claim 12  where n is from about 10 to about 20 and G is an alkyl group of 12 to 24 carbon atoms.  
     
     
         15 . A terpolymer according to  claim 12  where the weight:weight ratio acrylamide and/or methacrylamide:acrylic acid and/or methacrylic acid monomer units is from about 4:1 to about 1:4.  
     
     
         16 . A terpolymer according to  claim 12  where the weight:weight ratio of acrylamide and/or methacrylamide:acrylic acid and/or methacrylic acid monomer units is from about 2:1 to about 3:1.  
     
     
         17 . A terpolymer according to  claim 12  where the alkyl alkoxylate allyl ether monomer units are up to about 10% by weight of the terpolymer.  
     
     
         18 . A terpolymer according to  claim 12  where the alkyl alkoxylate allyl ether monomer units are up to about 5% by weight of the terpolymer.  
     
     
         19 . A terpolymer according to  claim 12  where the terpolymer has a weight average molecular weight of between about 20,000 and about 80,000.