Water-based coolant

Abstract

A water-based coolant contains: at least one inorganic acid salt selected from among carbonate, hydrogen carbonate, sesquicarbonate, phosphate, borate, molybdate and tungstate; and a metal corrosion inhibitor. The water-based coolant is excellent in cooling performance and unlikely to cause corrosion of a metal material to be cooled. Therefore, the water-based coolant is suitably usable as a quenchant or a cutting oil.

1 . A water-based coolant comprising:
 at least one inorganic acid salt selected from the group consisting of a carbonate, a hydrogen carbonate, a sesquicarbonate, a phosphate, a borate, a molybdate and a tungstate; and   a metal corrosion inhibitor.   
     
     
         2 . The water-based coolant according to  claim 1 , wherein the metal corrosion inhibitor comprises at least one compound selected from the group consisting of a benzotriazole compound, a benzimidazole compound, a benzothiazole compound and a benzothiadiazole compound. 
     
     
         3 . The water-based coolant according to  claim 1 , further comprising a bactericide. 
     
     
         4 . The water-based coolant according to  claim 3 , wherein a content of the bactericide is in a range of from 0.001 mass % to 0.5 mass % of a total amount of the coolant. 
     
     
         5 . The water-based coolant according to  claim 1 , wherein a content of the inorganic acid salt is in a range of from 1 mass % to 20 mass % of a total amount of the coolant. 
     
     
         6 . The water-based coolant according to  claim 1 , wherein a content of the metal corrosion inhibitor is in a range of from 0.01 mass % to 1 mass % of a total amount of the coolant. 
     
     
         7 . The water-based coolant according to  claim 1 , wherein the inorganic acid salt comprises an inorganic acid metal salt. 
     
     
         8 . The water-based coolant according to  claim 7 , wherein the inorganic acid salt comprises at least one of a sodium salt, a potassium salt, a calcium salt and a magnesium salt. 
     
     
         9 . The water-based coolant according to  claim 1 , wherein the inorganic acid salt is the phosphate, which comprises at least one of an orthophosphate, a hydrogenphosphate, a dihydrogenphosphate, a polyphosphate and a metaphosphate. 
     
     
         10 . A quenching oil or a cutting oil, comprising the water-based coolant according to  claim 1 .