Influences of γ and δ Precipitations on the Microstructural Properties of 718 Alloy through HIP, Solid-Solution, and Different Aging Heat Treatments

In our previous work, the parameters of solid-solution treatment for 718 alloy were discussed The results showed that a solution temperature of 1020 degrees C is optimum The Laves and delta phase can complete solution after 1020 degrees C, 1 h solid-solution treatment The aim of this stud) is to discuss the effect of various aging treatments for as-HIP treated 718 alloy In the experiment seven different aging treatments were used 720 degrees C for 2 4 8 and 16 h furnace cooled to 620 degrees C soak for 811 and air cooled to room temperature 720 degrees C for 811 furnace cooled to 620 degrees C, soak for 2 4 8 and 16 h induce cooled to room impel more Experimental results showed that 1020 degrees C solid-solution 720 degrees C for 8 h and 620 degrees C for 4 h of aging treatment for as-I-HP treated 718 alloy is optimum All the precipitations are MC carbides the dimension of gamma' precipitations is 30 41 nm which with a maximum tensile strength (1407 2 MPa) and elongation (14 5%) at room temperature [doi 10 2320/matertrans M2010138]