Question

For the Cu-Ag phase diagram, answer the following. Label the figure and add is part of your answer sheet........ ...(11 points) a) What is the eutectic temperature and composition? (1 point) b) In the context of this diagram, what does the symbol B represent? (1 point) c) Assume slow cooling and that equilibrium conditions exist for the alloy for 70 wt% Ag – 30 wt% Cu. If this is being cooled from 1000 °C, when will the first solid form and what composition would the solid have. (2 points) d) At the same composition listed above, List all the phases and their compositions at 600 °C. (2 points)

Answer 1

Eutectic point is the point where liquid metal Directly gets converted into two phase solid mixture.

This point can be seen at composition of 71.9% Ag in our diagram , where liquid metal is changing its phase directly to Alpha + Beta phase mixture.

Further solution is given in the image below ::

Liquid IL) Liquides Lt & LAR a. ß 779°C Eutectic Temperature (6) 'B' Represent the &+B 81.Ag 70%. Ag Composition (a) Eutectic Temperature = 779°C [71.9%. Ag Eutectic composition - 721, Agen 71.97.Ag Allotropic (solid) 2). Eutectic [L*+p Ag & 28.1t.lu Cu-Ag phase of Mixture 70% Agg (7194 - Ag), composition falls betor Euclectic composition 1374) » so upon equal to Will Become upon Cooling, When Temperature Line Liquidus Corresponding Temperature first solid Phase (&) to 70%. Ag, Will? Start to form Solid Willy have read 8%.Ag 92% Cu (x-Phase Composition

(4) Liquid L ath LAPA 7790 600°C Pro Extatott Extentic a LTB >gol.Ag 42. to. Ag 31.25). Ag Ag 'Pro Entretien Eutectica 3% at at 600°C! a & B Both will be Present in Alternate Layer With some Amount of Pro Eatectonta Eutectica (Alternate Layers of a & ß 7 172 2+B booc 17.94 37, 81 Ag 704 Ag gby, ng .. at 600°C :- 96-70 Total x./. -xlas = 27.964 96-3 %B 100 27.96 7210.4.). Ande 4. Prona o 71.9-70 TOO 71.9-8 2.974 A D'y a phase Toten 2-Prod = 27.96-2197 = $ 4.990), They Made After Ententic Temperature

620 f Microstructure Pro Entertic a Pro-d) (or Pro < Alternate Layers of x &ß Phases
Hope you got the concept well..!!!