Answer Happy

Question #3 a)Suppose that homogeneous nuclei formed during a phase transformation are cubic in shape rather than spherical. If a is the dimension of the cube and Tm (140∘C) is the melting point of the solid which cooled down to T=80∘C. Given: The surface tension γ=0.065 N/m and Latent heat of fusion =40.7 kJ/mol i. Calculate the critical nucleus size. ii. Calculate the critical free energy, required to form a stable nucleus. b) Considering the Time-Temperature-Transformation diagram, i. Draw the diagram and using that, explain the condition in which amorphous phase is grown. ii. Using the above diagram, explain the critical cooling rate.