Cutting fluid for steel-grit die-cast aluminium and preparation method thereof

A cutting fluid for steel-grit die-cast aluminium is prepared from the following raw materials in parts by weight: 4-5 parts of boric acid, 12-15 parts of glycerin, 1-2 parts of triethanolamine, 4-6 parts of dimethicone, 10-12 parts of glycol, 2-3 parts of aluminium dihydrogen phosphate, 1-2 parts of citric acid, 0.5-1.0 part of 2, 2, 4-trimethyl-1,3-pentanediolmono(2-methylpropanoate), 4-5 parts of polyoxyethylene octylphenol ether, 6-8 parts of an auxiliary agent and 200 parts of water. The cutting fluid provided by the invention has excellent lubricity, antirust property and settlement property, is improved in film forming performance by employing 2, 2, 4-trimethyl-1,3-pentanediolmono(2-methylpropanoate), can from a protective film on the surface of metal, and has extremely good protective effect especially on steel grit; the cutting fluid is improved in wear resistance by utilizing aluminium dihydrogen phosphate; and the cutting fluid has no toxic substances such as formaldehyde, nitrites and the like, is small in harm to human body and environment, and also helps to save economic cost.