CHEMICAL MILLING OF HIGH TUNGSTEN CONTENT SUPERALLOYS

摘要

Chemical Milling of High Tungsten Content Superalloys Chemical milling of cast superalloys having high tungsten contents is advantageously accomplished with an etchant which consists by volume percent of 40-60 concentrated HNO3, 0.6-0.8 concentrated HF, 40-70 H2O, with which is included at least 0.008 moles/liter CuSO4 and 0.0016-0.025 moles/liter FeCl3. Preferably the molar ratio of CuSO4 to FeCl3 is 2:1 and etching is accomplished in the range 50-80.degree.C.