Determination of thermophysical and structural properties of nickel super-alloy

Abstract

In this work the differential thermal analysis (DTA) was selected for the study of 718Plus super-alloy. Particular attention was paid to determination of the phase transformation temperatures (liquidus, γ´ precipitation temperature, etc.). Almost at all temperatures of samples an undercooling was observed. Shifting of almost all temperatures was observed in the heating/cooling mode towards higher values with an increasing rate of heating, lower values with the increasing cooling rate. On the basis of DTA and structural analysis it may be stated that development of phase transformations will probably correspond to the following scheme: melting → γ phase; melting → γ + MC (NbC, TiC); melting + MC → γ + Laves + σ; γ → γ´ (γ´´).

Keywords

• Ni super-alloy
• differential thermal analysis
• thermophysical properties
• structural properties