THE INFLUENCE OF COLD, WARM AND HOT DEFORMATION ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF INCONEL 718 SUPERALLOY

This study systematically examines the influence of precipitation on the microstructural and mechanical properties of Inconel 718 superalloy in as-received, solution heat-treated, peak-aged, and overaged conditions. Cold, warm, and hot deformation tests were performed at 25 degrees C, 400 degrees C and 800 degrees C using a constant strain rate of 5.55x10-4 s-1. The results indicated dynamic strain aging during warm deformation at 400 degrees C in all investigated conditions. However, at temperatures above 400 degrees C, a pronounced reduction in strength was observed, accompanied by a corresponding increase in elongation for most conditions. Notably, the solution heat-treated samples exhibited anomalous behavior, showing an increase in Rp0.2 after deformation at 800 degrees C. This suggests the occurrence of dynamic precipitation during hot deformation in the solution heat-treated samples.