For the solidification of nickel, calculate the critical radius r* and the activation energy ΔG* if nucleation is homogeneous. Values for the latent heat of fusion and surface free energy are -2.53×109 J/m3 and 0.255 J/m2, respectively. The supercooling value ΔT for the homogeneous nucleation of Ni is 319 oC. The melting point for Ni is 1455 oC.

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Q: 5

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Solidification of metals

The term solidification indicates the conversion of material from the state of liquid to the state of solid. The solid-state is more compact and rigid than liquid, and the solidification indicates the transformation of material from a random state to a more compact and crystalline form. The point at which dendrite formation in liquid starts taking place is referred to as the solidification point.