Solidification of Be-free Ni-based dental alloy
(1. Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia;
2. Department of Materials Engineering, School of Engineering, University of Sao Paulo, 12602-810 Lorena, Sao Paulo, Brazil)
2. Department of Materials Engineering, School of Engineering, University of Sao Paulo, 12602-810 Lorena, Sao Paulo, Brazil)
Abstract: A novel, Nb- and Si-rich and Be-free Ni-based alloy was cast by two methods of investment casting and continuous casting to study the microstructure evolution during solidification and its mechanical properties. The solidification of the alloy started with the primary crystallization of FCC-γ, followed by a binary eutectic reaction, with the formation of a heterogeneous constituent: FCC-γ+G-phase, which replaced the low-melting eutectic (FCC-γ+NiBe) in the Be-bearing alloys. AlNi6Si3 and γ′ formed during the terminal stages of solidification by investment casting, while the formation of AlNi6Si3 was suppressed by continuous casting. The Scheil solidification model agreed very well with the experimental results.
Key words: solidification; nickel alloy; continuous casting; investment casting; microstructure; dental alloy