METHOD FOR EVALUATING CORROSION RESISTANCE OF WATER SOLUBLE CUTTING OIL FOR WORKING ALUMINUM AND ALUMINUM ALLOY

摘要

PURPOSE:To realize a simple and quick evaluation method having high correlativeness with the actual condition by immersing the entire part of turning scrap into a dilute liquid then removing part of the dilute liquid and resting the scrap for a prescribed period at a prescribed temp. while said scrap is half immersed in the dilute liquid. CONSTITUTION:The turning scrap of aluminum or aluminum alloy and the dilute liquid of a water soluble cutting oil are put into a vessel which can maintain airtightness, for example, Erlenmeyer flask to immerse the entire part of the scrap in the dilute liquid. Part of the dilute liquid is then removed by a method such as decantation so that the turning scrap is half immersed in the dilute liquid. A cap is put on the vessel and the hermetic state is maintained in the vessel, then the vessel is rested for 24-48hr in a thermostatic chamber kept at 40-70 deg.C atmosphere temp. The coloration, the formation of zinc white rust, etc. on the surface of the turning scrap are visually observed. The coloration and the formation of zinc white rust are not admitted even with the dilute liquid which causes the coloration and the formation of zinc white rust in an actual line if the temp. is <=40 deg.C. The coloration is admitted even with a fresh liquid and the correlativeness of the result of the discrimination with the actual line is poor if the temp. exceeds 70 deg.C.