Use the Fe-C phase diagram at the end to answer the following questions. A 0.55 wt%...

  

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Use the Fe-C phase diagram at the end to answer the following questions. A 0.55 wt% carbon steel is slow cooled from 1000°C to a temperature slightly below 727°C. In the final structure: (a) Sketch and label a typical microstructure showing all phases & micro-constituents that would be present at 720 °C (b) Indicate the phase or phases present and the composition of each phase, and calculate how much of each phase is present. (c) At the same temperature determine the fractions of (proeutectoid) ferrite and pearlite. (d) What phase would be present if the sample is very rapidly quenched instead from 1000°C to room temperature? (e) Can this phase be found on the Fe-C diagram, and if not, why not? Temperature (°C) 0 1600 1400 1200 1000 1538°C 600 800 a 400 0 912°C (Fe) +2 8 Y 1493°C 1394°C y, Austenite 0.76 0.022 a, Ferrite 5 y + L 2 2.14 Composition (at% C) 15 10 1147°C a + Fe3C L 3 4 Composition (wt% C) 4.30 y + Fe3C 727°C 20 Cementite (Fe3C) 5 6 25 2500 2000 1500 1000 6.70 Temperature (°F) 1. Use the Fe-C phase diagram above to answer the following questions. A 0.55 wt% carbon steel is slow cooled from 1000°C to a temperature slightly below 727°C. In the final structure: a. Sketch and label a typical microstructure showing all phases & micro-constituents that would be present at 720 °C. b. Indicate the phase or phases present and the composition of each phase, and calculate how much of each phase is present. c. At the same temperature determine the fractions of (proeutectoid) ferrite and pearlite. d. What phase would be present if the sample is very rapidly quenchedinstead from 1000°C to room temperature? e. Can this phase be found on the Fe-C diagram, and if not, why not? Use the Fe-C phase diagram at the end to answer the following questions. A 0.55 wt% carbon steel is slow cooled from 1000°C to a temperature slightly below 727°C. In the final structure: (a) Sketch and label a typical microstructure showing all phases & micro-constituents that would be present at 720 °C (b) Indicate the phase or phases present and the composition of each phase, and calculate how much of each phase is present. (c) At the same temperature determine the fractions of (proeutectoid) ferrite and pearlite. (d) What phase would be present if the sample is very rapidly quenched instead from 1000°C to room temperature? (e) Can this phase be found on the Fe-C diagram, and if not, why not? Temperature (°C) 0 1600 1400 1200 1000 1538°C 600 800 a 400 0 912°C (Fe) +2 8 Y 1493°C 1394°C y, Austenite 0.76 0.022 a, Ferrite 5 y + L 2 2.14 Composition (at% C) 15 10 1147°C a + Fe3C L 3 4 Composition (wt% C) 4.30 y + Fe3C 727°C 20 Cementite (Fe3C) 5 6 25 2500 2000 1500 1000 6.70 Temperature (°F) 1. Use the Fe-C phase diagram above to answer the following questions. A 0.55 wt% carbon steel is slow cooled from 1000°C to a temperature slightly below 727°C. In the final structure: a. Sketch and label a typical microstructure showing all phases & micro-constituents that would be present at 720 °C. b. Indicate the phase or phases present and the composition of each phase, and calculate how much of each phase is present. c. At the same temperature determine the fractions of (proeutectoid) ferrite and pearlite. d. What phase would be present if the sample is very rapidly quenchedinstead from 1000°C to room temperature? e. Can this phase be found on the Fe-C diagram, and if not, why not?