Heat treatment effect on CNC turning of Incoloy 800H superalloy

Nuclear power plant components, high-temperature furnace, and most of the nuclear reactors are in need of high creep rupture which can be attained by Incoloy 800H superalloy. Based on this, the present research work is aimed to relate the microstructure, mechanical, and machinability of Incoloy 800H in various conditions, namely, solution treated, heat-treated with air cooling, and heat-treated with furnace cooling. The samples were initially heated till 975 degrees C after solution treated and then subjected to the aforesaid heat treatments. The optical microstructures revealed that the fine grains' structure was obtained in the air-cooled sample, whereas coarse grain structure was obtained in a furnace-cooled sample. The heat-treated samples were machined using CNC dry turning process and the machining parameter effects on the machinability aspects were studied, investigated, and reported. Experimental investigations explained clearly that the machinability aspects were significantly influenced by the cooling medium. Furnace-cooled sample had shown improvement in mechanical and machinability performances.