Microstructure and Properties of Incoloy825 Alloy after Solution at Different Temperatures

The microstructure, mechanical properties and corrosion resistance of Incoloy825 alloy after solution at different temperatures were researched by scanning electron microscope, transmission electron microscope, brinell hardness tester, tensile test machine. The results show that the grain size did not change after solution at 980-1 050℃, but grain size obviously increased when solution temperature was above 1 050℃. The hardness and tensile strength decreased but the elongation increased with the increase of solution temperature. The precipitate phase along grain boundary consisted of M₂₃C₆ carbide with Cr and Mo and intermetallic compound with Cr, Ni, Fe and Mo. The amount of precipitate phase increased initially and decreased afterwards with the increase of solution temperature. When solution temperature was 1 015℃, the amount of precipitate phase reached to the maximum, while the intergranular corrosion resistance was the worst.