Ni-based superalloys are usually employed in industrial applications where good mechanical performance, corrosion and oxidation resistance at high temperatures is required. Samples collected from a gas turbine rotor blade were used in the present study. The X-ray photoelectron spectroscopy (XPS) and inductive coupled plasma (ICP) techniques were used to identify and quantify the elements in the alloy. simultaneous thermal analysis (STA) has been used to study the behavior of the alloy during the heat treatment from room temperature to 1450 degreesC, under argon and air atmospheres. Heat capacity has been evaluated and two solid-solid transitions have been identified below 1400 degreesC. A small oxidative process was identified at temperatures over 1150 degreesC.