Abstract
Relation between solidification conditions and solidification structures and solute distribution is examined by quenching the nickel-aluminum bronzes during unidirectional solidification. Equiaxed structures form as the liquid temperature gradient becomes lower and solidification rate larger. Formation of equiaxed structures is due to the presence of constitutional supercooling. Secondary dendrite arm spacing d is represented as : d=c·θn, where c is constant, θ is time spent from the passage of the solid-liquid interface prior to quench, and n is constant and approximately 0.3 when the solidification rate is low. Equilibrium distribution coefficients for Al, Fe, Ni and Mn are 1.13, 2.50, 1.51 and 0.57, respectively.
