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Which of the following is a single phase that can occur in steels: a. CM b. eutectoid

Which of the following is a single phase that can occur in steels: a. CM b. eutectoid c. Al-Cu solid solution d. pearlite e. carbon. 2. All steels used in the temperature range from 0° to 100° C must contain: a. Fe and C b. Fe and 6.67 w/o C c. FE d. MAR e. AUS.

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Which of the following is a single phase that can occur in steels: a. CM b. eutectoid

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  1. Which of the following is a single phase that can occur in steels: • a. CM • b. eutectoid • c. Al-Cu solid solution • d. pearlite • e. carbon

  2. 2. All steels used in the temperature range from 0° to 100° C must contain: • a. Fe and C • b. Fe and 6.67 w/o C • c. FE • d. MAR • e. AUS

  3. 3. A 1020 steel, slowly cooled to room temperature, contains: • a. roughly equal amounts of FE and P • b. 0.20% C • c. all AUS • d. all MAR • e. all Pearlite

  4. 4. Carbon in steels at equilibrium at room temperature can be found in these phases and/or microconstituents: • a. FE, P, CM • b. FE only • c. CM only • d. P only • e. FE, graphite

  5. 5. Which of the following is NOT a class of stainless steel? • a. pearlitic • b. martensitic • c. ferritic • d. austenitic

  6. 6. Phases present in a hypereutectoid steel slowly cooled from the AUS phase: • a. FE, P • b. CM, P • c. FE, CM • d. CM, graphite • e. AUS, P

  7. 7. A 9160 steel is very rapidly quenched to a temperature 20° below the ms (40° above the mf) and held at this temperature for a month. The phases present are: • a. AUS, FE, CM • b. AUS, MAR • c. AUS, Bainite • d. MAR, P • e. MAR, FE, CM

  8. 8. One way to increase hardenability is to add alloy elements; which of these alloying elements does not latch onto C atoms to effect this increase? • a. V • b. W • c. Cr • d. Mo • e. None of the above

  9. 9. Which of the following will not form upon tempering a steel (the tempering time can vary): • a. AUS • b. transition Fe carbides • c. alloy carbides • d. FE • e. CM

  10. 10. Which of the following is a true statement: • a. AUS can be formed by appropriately heating any mixture of FE and CM • b. under equilibrium conditions, P can form at any temperature in the range 723° C down to room temperature (the reaction rate at lower temperatures would be extremely slow) • c. a martensitic steel must be tempered in order to form the austenite phase • d. tempering MAR for long periods at high tempering temperatures causes P to form • e. tempering MAR for long periods at high tempering temperatures causesproeutectoid FE to form

  11. 11. Estimate the strength of a 1020 steel heated treated so as to contain the equilibrium phases: a. 40 ksi b. 60 ksi c. 80 ksi d. 100 ksi e. 120 ksi

  12. 12. AUS can not be formed by heating which of the following to a sufficiently high temperature. • a. MAR • b. P • c. hypereutectoid steels • d. a 3% C cast iron • e. pure CM

  13. 13. We discussed a number of occasions in which AUS can be found at temperatures below 723° C. Which of the following is not a reason this is so: • a. diffusion rates in solids are slow • b. tempering is a time dependent process • c. the transformation to MAR is temperature dependent • d. some alloying elements have extensive solubilities in -Fe

  14. 14. Loss of brittleness in fresh MAR at the beginning of tempering is a direct result of a. the formation of AUS b. use of the correct austenitization temperature c. low hardenability d. formation of alloy carbide particles e. stress relief

  15. 15. WC tools are: • a. tool steels with sufficiently large amounts of tungsten and carbon in them to form WC upon heat treatment • b. formed upon carburization of a W- containing steel • c. formed by heating a mixture of WC and Co to a temperature high enough to melt the Co, which flows around the WC and holds it together when cooled • tool steels quenched by Water Cooling • formed by a process that makes extensive use of diffusion

  16. 16. When tempering martensite: • a. no atom movement is involved • b. the atoms of the alloy elements attract the carbon atoms • c. the Fe atoms of the alloy elements do not attract the C atoms • d. the carbon atoms aggregate to form large graphite areas in the steel

  17. 17. Which of the following does NOT control the position of the TTT curve? a. alloy element content b. %C c. AUS grain size d. heat treatment

  18. 18. Which is not a way to increase the hardenability of a steel: • a. increase carbon content • b. move TTT curves by decreasing the amount of alloying elements present • c. temper it first • d. increase the size of AUS grain size

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