A4:Alloying(Chapter4) 16points a Give the Gibbs phase rule.Identify all variables in this relation.(2.5 points) b) Construct a qualitative phase diagram for the three phases S,a and B as function of the solute content cB from the Gibbs free energy curves given at the four temperatures TI to T4.Indicate all phase fields.(5 points) c)How much is the solubility limit at T=OK?Explain your answer by drawing curves of the enthalpy H(c),the entropy S(c)and the Gibbs free energy G(c)as a function of the solute concentration c in a graph.(2.5 points) 少 Draw the unit cell of the ordered alloy compounds CuAu and Ni3Al.(2 points) e) How is the long range order parameter s defined(equation)?Give a relation and explain the different quantities appearing in it.Which range of values does this parameter take in case of an AB alloy?And for an AB3 alloy?Account for your answer using simple calculations.(4 points)4 A4: Alloying (Chapter4) 16points a) Give the Gibbs phase rule. Identify all variables in this relation. (2.5 points) b) Construct a qualitative phase diagram for the three phases S, α and β as function of the solute content cB from the Gibbs free energy curves given at the four temperatures T1 to T4. Indicate all phase fields. (5 points) c) How much is the solubility limit at T= 0K? Explain your answer by drawing curves of the enthalpy H(c), the entropy S(c) and the Gibbs free energy G(c) as a function of the solute concentration c in a graph. (2.5 points) d) Draw the unit cell of the ordered alloy compounds CuAu and Ni3Al. (2 points) e) How is the long range order parameter s defined (equation)? Give a relation and explain the different quantities appearing in it. Which range of values does this parameter take in case of an AB alloy? And for an AB3 alloy? Account for your answer using simple calculations. (4 points)