摘要 |
<p>A metal quenchant fluid which is a mixture of water and a polyalkylene glycol and a inhibitor is substantially nitrite free. The inhibitor is a soluble product obtained by mixing a carboxylic acid having 4 to 12 carbon atoms in the molecule, an amine such as an alkanolamine boiling above 150 DEG C. at atmospheric pressure and a copper chelating agent such as NN diethanol methylene benzotriazole.</p> |