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.

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.

Welding: Principles and Applications (MindTap Course List)

8th Edition

ISBN:9781305494695

Author:Larry Jeffus

Publisher:Larry Jeffus

Chapter26: Welding Metallurgy

Section: Chapter Questions

Problem 12R: What is a eutectic composition?

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