Pressure effect on the phase transitions in Ni-base multicomponent systems

Summary The phase transformations in the three Ni-base alloys at the temperature range up to 1500°C and at the pressure of 170 MPa were studied. Solidus, -phase dissolution/precipitation, carbides dissolution/precipitation and liquidus temperatures are established. Multiple exceeding of the Ni-base alloys characteristic temperatures pressure coefficients over metal components ones (up to 10 times) is observed both at the heating and cooling scans during the experiments on the differential barothermal analysis. On the DBA curves had been obtained at 170 MPa, there are from two to three peaks, which connected with the carbides dissolution/precipitation, while on the each conventional DTA curve there was merely one carbide thermal effect. The liquidus temperature pressure coefficients correlate with the Ni melting point pressure coefficient.