3. Define pearlite (2 marks) 4. What are the differences between a Phase and a Microconstituent? Give an example for each. (4 marks) 5. What happens at the eutectic and eutectoid reaction points? (3 marks) Total Marks: / 16 1. Label the following on the Iron-Carbon phase diagram below: a) The austenite region b) The ferrite & pearlite and cementite & pearlite regions c) Circle and label the Eutectic and Eutectoid reaction points d) The lower critical temperature line (4 marks) e) On the bottom of the diagram, identify the definition of "steel" and "cast fron" with respect to the carbon content (% weight) [C] 1600- 1400- 1200- 1000- 800- 600- 400- 200- 0 2 6 [%] 2. Answer the following questions relating to the Iron-Carbon phase diagram (on the previous page) a) At what temperature range is a steel with 0.5% C in the austenite phase? (1 mark) b) For a steel with 0.5% C, at what temperature does iron have a body centered cubic (BCC) lattice structure? (1 mark) c) For a steel with 0.5% C, what is the microstructure of steel at room temperature? 3. Define pearlite (1 mark) (2 marks) 4. What are the differences between a Phase and a Microconstituent? Give an example for each. (4 marks)