Pt(Al)can be rendered supersaturated and aged to cause continuous precipitation of the stable phase Pt3Al.In binary Al(Cu)alloys continuous precipitation of the stable phase CuAl2 can occur.In this case typical lattice parameters are 0.404nm. for die aluminum solid solution and 0.607nm,0.607nm,0.487nm for me complex tetragonal unit cell (12 atoms)of CuAl2. Using the concepts of classical nucleation theory discuss,in detail,the transformations you would predict to occur when terminal solutions of these alloys are slowly cooled to room temperature. 16.Misruns,cold shuts,and incomplete fills are casting defects frequently attributed to inadequate fluidity. (a)Define fluidity relevant to cold mold casting processes such as the sand or permanent mold casting methods.Identify the casting variables which control fluidity and indicate the expected interrelation between the casting variables and fluidity (b)Define fluidity relevant to hot mold casting processes such as the investment casting processes.Identify the casting variables which control fluidity and indicate the expected interrelations between the casting variables and fluidity. Where possible,provide quantitative relations between fluidity and the casting variables in responding to both parts(a)and(b). 17.Consider two ferrous alloys which are deformed at 800C(0.60 Tm).One is an annealed,coarse grained,fully ferritic (bcc)iron with a fairly uniform grain size which has an average grain diameter of 70 4m.The other is a microduplex alloy which has an average grain diameter of2m and consists of 30 volume percent austenite and 70 volume percent ferrite. (a)Both of these materials are crept at constant stress such that the steady-state strain rate is approximately 10-5 s-1.Sketch the resulting time-elongation plots.Use the same set of axes for both curves. (b)Sketch the stress versus steady-state strain rate relationship for each material.Use the same set of axes for both curves.Be precise and describe the physical origins of the behavior you show. (c)Imagine now that you will make a 5-layer laminated composite (alternating sheets)of these two steels,with greater than 80 volume-percent of the duplex alloy.Draw the tensile stress versus steady-state strain rate relationship that you would expect for this composite material loaded in a tensile direction which is parallel to the interfaces.What assumptions must you make in making this graph? (d)Using the plot above,sketch the relationship that you expect to see between tensile elongation and creep stress for the laminated composite:(i)if 80% duplex alloy,(ii)if 60%duplex alloy.State what assumptions you must make (assume constant stress creep).Pt(Al) can be rendered supersaturated and aged to cause continuous precipitation of the stable phase Pt3Al. In binary Al(Cu) alloys continuous precipitation of the stable phase CuAl2 can occur. In this case typical lattice parameters are 0.404nm. for die aluminum solid solution and 0.607nm, 0.607nm, 0.487nm for me complex tetragonal unit cell (12 atoms) of CuAl2. Using the concepts of classical nucleation theory discuss, in detail, the transformations you would predict to occur when terminal solutions of these alloys are slowly cooled to room temperature. 16. Misruns, cold shuts, and incomplete fills are casting defects frequently attributed to inadequate fluidity. (a) Define fluidity relevant to cold mold casting processes such as the sand or permanent mold casting methods. Identify the casting variables which control fluidity and indicate the expected interrelation between the casting variables and fluidity. (b) Define fluidity relevant to hot mold casting processes such as the investment casting processes. Identify the casting variables which control fluidity and indicate the expected interrelations between the casting variables and fluidity. Where possible, provide quantitative relations between fluidity and the casting variables in responding to both parts (a) and (b). 17. Consider two ferrous alloys which are deformed at 800°C (0.60 Tm). One is an annealed, coarse grained, fully ferritic (bcc) iron with a fairly uniform grain size μ which has an average grain diameter of 70 m. The other is a microduplex alloy μ which has an average grain diameter of 2 m and consists of 30 volume percent austenite and 70 volume percent ferrite. (a) Both of these materials are crept at constant stress such that the steady-state strain rate is approximately 10-5 s-1. Sketch the resulting time-elongation plots. Use the same set of axes for both curves. (b) Sketch the stress versus steady-state strain rate relationship for each material. Use the same set of axes for both curves. Be precise and describe the physical origins of the behavior you show. (c) Imagine now that you will make a 5-layer laminated composite (alternating sheets) of these two steels, with greater than 80 volume-percent of the duplex alloy. Draw the tensile stress versus steady-state strain rate relationship that you would expect for this composite material loaded in a tensile direction which is parallel to the interfaces. What assumptions must you make in making this graph? (d) Using the plot above, sketch the relationship that you expect to see between tensile elongation and creep stress for the laminated composite: (i) if 80% duplex alloy, (ii) if 60% duplex alloy. State what assumptions you must make (assume constant stress creep)