The ATD thermal analysis of selected nickel superalloys

The study presents the results of the ATD thermal analysis made on selected nickel alloys used by WSK Rzeszów for parts of aircraft engines. The aim of the studies was investigation of solidification parameters, especially Tlik and Tsol. The said parameters are very important in the determination of pouring temperature and maximum operating temperature of castings. Another important technical information is the quality of "master heat" ingots, examined for the stability of chemical composition and presence of different impurities. It has been concluded that the pouring temperature of CMSX-4 and MAR-247 alloys should be comprised in a range from 1470 to 1480°C, while for the remaining alloys the recommended range of pouring temperatures is from 1440 to 1450°C. Examinations have also proved that some batches of the supplied ingots are contaminated with non-metallic impurities, located mainly in the region of shrinkage cavities.