The following data apply to the binary system of A and B: Melting point of pure...

 

Transcribed Image Text:

The following data apply to the binary system of A and B: Melting point of pure A = 1050°C Melting point of pure B = 1900°C At 1250°C, the a solid solution (containing 50% of B), the B solid solution (containing 80% of B) and liquid (containing 30% of B) are in three-phase equilibrium. At room temperature, the maximum solubility of B in the a phase is 30% and the maximum solubility of A in the B phase is 10%. (i) Sketch the phase diagram of A and B, showing the phases present in each area of the diagram. (ii) What is the reaction that takes place at 1250°C? (iii) What are the weight fractions of the phases present in a material of overall composition 75% B, at 1251°C, 1249°C and at room temperature (RT)? Answer: (ii) At 1251°C, =0.1, fa = 0.9; at 1249°C, fa= 0.167, f = 0.833; and %3D at RT, fa = 0.25, fs = 0.75. %3D The following data apply to the binary system of A and B: Melting point of pure A = 1050°C Melting point of pure B = 1900°C At 1250°C, the a solid solution (containing 50% of B), the B solid solution (containing 80% of B) and liquid (containing 30% of B) are in three-phase equilibrium. At room temperature, the maximum solubility of B in the a phase is 30% and the maximum solubility of A in the B phase is 10%. (i) Sketch the phase diagram of A and B, showing the phases present in each area of the diagram. (ii) What is the reaction that takes place at 1250°C? (iii) What are the weight fractions of the phases present in a material of overall composition 75% B, at 1251°C, 1249°C and at room temperature (RT)? Answer: (ii) At 1251°C, =0.1, fa = 0.9; at 1249°C, fa= 0.167, f = 0.833; and %3D at RT, fa = 0.25, fs = 0.75. %3D