CONFIDENTIAL 202109/EGE301/A (b) Figure 6 shows the eutectoid portion of Fe-Fe3C phase diagram. In particular for...

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CONFIDENTIAL 202109/EGE301/A (b) Figure 6 shows the eutectoid portion of Fe-Fe3C phase diagram. In particular for Fe-0.35% C alloy, determine the temperature at which austenite first begins to transform on cooling. (ii) the primary microconstituent that form. [2 marks] [2 marks] [2 marks] (iii) the composition and amount of each phase present at 728 C. (iv) the composition and amount of each phase present at 726 C. (v) the composition and amount of each microconstituent present at 726C. [2 marks] [2 marks] Temperature (C) 1000 800 +1 0.0218 0.77 600- Fe3C + FezC 400- 727C Fe3C Fe3C Hypo Hyper 200Fe 0.4 0.8 1.2 6.67 Pearlite Weight percent carbon Figure 6: The eutectoid portion of the Fe-FeC phase diagram. Pearlite (c) A steel contains 18% cementite and 82% ferrite at room temperature. Evaluate the carbon content of the steel. Is the steel hypoeutectoid or hypereutectoid? [4 marks] CONFIDENTIAL 202109/EGE301/A (b) Figure 6 shows the eutectoid portion of Fe-Fe3C phase diagram. In particular for Fe-0.35% C alloy, determine the temperature at which austenite first begins to transform on cooling. (ii) the primary microconstituent that form. [2 marks] [2 marks] [2 marks] (iii) the composition and amount of each phase present at 728 C. (iv) the composition and amount of each phase present at 726 C. (v) the composition and amount of each microconstituent present at 726C. [2 marks] [2 marks] Temperature (C) 1000 800 +1 0.0218 0.77 600- Fe3C + FezC 400- 727C Fe3C Fe3C Hypo Hyper 200Fe 0.4 0.8 1.2 6.67 Pearlite Weight percent carbon Figure 6: The eutectoid portion of the Fe-FeC phase diagram. Pearlite (c) A steel contains 18% cementite and 82% ferrite at room temperature. Evaluate the carbon content of the steel. Is the steel hypoeutectoid or hypereutectoid? [4 marks]