11:55 PM 90 0 1.5KB/S D24 { ASSIGNMENT 2 PHASE DIAGRAM... : ASSIGNMENT PHASE DIAGRAM AND PHASE TRANSFORMATION QUESTION I (20 marks) 1. An alloy of 30 wt% Pb ind 70 % Sn is slowly come from 250 C to 27. see w1 Figure below). Is this alloy hypoeutectic or hypercutectic? (m) What is the composition of the fint solid to form? () What are the amounts and compositions of each phase that is present at 1830 +AT fiv) What are the amounts and composition of each phase that is presentat 1930- ATY (v) What are the amounts of cach phase present at room temperature! -- F Q2 (a) Plumbum-Stamm Phase Diagram 2. Explain the concepts of Time Temperature Transformation (TTT) curves. How do they help in understanding the various transformation products in steel 3. Justify how the following heat treatment can be conducted, quoting approximates , temperatures and cooling rate Normaliting of a plain carbon steel containing 0.4 wt%C Hardening of a plain carbon steel containing 0.8 wt%C. QUESTION 2/20 marks) (1) Fig below shows equilibrium phase diagram of copper-silver phase diagram. For 30% Ag and 70% Coat 900 C. determine: (1) The phases present () The composition of each phase (ii) The relative mana fraction of each phase (2) Briefly explain why upon solidification, an alloy of eutectic composition forms a microstructure consisting of altermuning the two solid phases 1 of 3 100 2000 W 00