The structures formed during equilibrium solidification and sintering process of nickel base superalloy IN-100 were investigated.
The results obtained were as follows:
(1) During equilibrium solidification, four kinds of reaction, P1 (1610-1583K), P2 (1583-1546K), P3 (1546-1528K), P4 (1528-1483K), were detected by differential thermal analysis. Primary γ and eutectic γ-γ' were formed by the reactions, P1 and P2 respectively. The γ phase was formed by the P3 reaction, and the Zr rich and γ phases were formed by the P4 reaction.
(2) During sintering process, γ' and γ were formed by the 1st (1498-1523K) melting reaction. γ was formed by the 2nd (1523-1548K) melting reaction, and γ-γ'eutectic was formed by the 3rd (1548-l572K) melting reaction.
(3) Phases formed by the melting reactions, 2nd and 3rd, during sintering process corresponded to those formed by the reactions, P3 and P2 during equilibrium solidification, respectively.
(4) Phases formed by the 1st melting reaction during sintering process were different from those formed by the P4 reaction during equilibrium solidification, because IN-100 powder used in this study was prepared by rapid cooling.