Given the time-temperature transformation diagram on page 5, what would be the phases present for a...

 

  

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Given the time-temperature transformation diagram on page 5, what would be the phases present for a 4340 steel with no alloying elements? Use the bottom of this page to show any work, including any phase diagram-related calculations (worth 5 pts.). A) cooled in air at 2°C/minute to 650°C, then quenched to room temperature B) quenched in cold water directly to room temperature in 0.1 second C) quenched in cold water directly to room temperature in 0.1 second, then heated to 425°C and held there for 1000 seconds, and finally quenched to room temperature D) quenched in cold water to 650°C in 0.1 second, then held at 650°C for 1000 seconds, then quenched to room temperature E) quenched in cold water to 600°C in 0.1 second, then held at 600°C for 5 seconds, then quenched to 350°C, held at 350°C for 60 seconds, and finally quenched to room temperature F) quenched in cold water to 550°C in 0.1 second, then held at 550°C for 5 seconds, then quenched to room temperature G) quenched in cold water to 380°C in 0.1 second, then held at 380°C for 100 seconds, then quenched to room temperature Necessary Steel Phase Diagram Calculations (continued on p. 6 if necessary): 302 Chapter 10/Phase Tranformations in Metals t 10.02. Tural alor diagram for ally steel (ype 4340) A. austen, lie P. pearlie: Mart be (Adapted from I Boyer, Edis, Atherof Fathermal Tr and Cooling Tranformation Di Annican Soci ty for Metals, 1977. p 181) d+y 19.14 0,40whic r 730°C di Fez C 6.77 707°C O aradway is 707°C instead of 727°C/ 800 700 600 500 400- 300 200 100- of 1 Electd temperature Mistart M (50%) 10 ·Pesc @6.69 wt.20 C 10⁰ 10 Time (s) 10 10⁰ 1400 1200 1000 800 600 400 200 10⁰ Temperature (°F) Wt.7. C The presence of alloying elements other than carbon (e.g. Cr. Ni, Mo, and W) may cause significant changes in the positions and shapes of the curves in the isothermal transformation diagrams. These include (1) shifting to longer times the nose of the austenite-to-pearlite transformation (and also a proeutectoid phase nose, it For the phase of diagram-related may be observed by comparing Fig of a separate bainite nose. These alterations calculations the art of proeutectoid product, approximate 4340 steel as being 1040 steel except that the evtec toid temp Figures 10.13 10.14, which are isothermal transformation diagrams for carbon and alloy steels, respectively Steels in which carbon is the prime alloying element are termed plain carbon steels, whereas alloy steels contain appreciable concentrations of other elements, including those cited in the preceding paragraph. Chapter 12 tells more about the classification and properties of ferrous alloys almest the same as EXAMPLE PROBLEM 10.1 Using the isothermal transformation diagram for an iron-carbon alloy of eutee toid composition (Figure 10.13), specify the nature of the final microstructure (in terms of microconstituents present and approximate percentages) of a small specimen that has been subjected to the following time-temperature treatments In each case assume that the specimen begins at 760°C (1400°F) and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure Temperature (°C) 1700 1500 1300 1100 900 C- 700 500 14 $ 0 4.5% (T) Cu 20 40 Composition (wt% Cu) L TICU Tu 60 Given the time-temperature transformation diagram on page 5, what would be the phases present for a 4340 steel with no alloying elements? Use the bottom of this page to show any work, including any phase diagram-related calculations (worth 5 pts.). A) cooled in air at 2°C/minute to 650°C, then quenched to room temperature B) quenched in cold water directly to room temperature in 0.1 second C) quenched in cold water directly to room temperature in 0.1 second, then heated to 425°C and held there for 1000 seconds, and finally quenched to room temperature D) quenched in cold water to 650°C in 0.1 second, then held at 650°C for 1000 seconds, then quenched to room temperature E) quenched in cold water to 600°C in 0.1 second, then held at 600°C for 5 seconds, then quenched to 350°C, held at 350°C for 60 seconds, and finally quenched to room temperature F) quenched in cold water to 550°C in 0.1 second, then held at 550°C for 5 seconds, then quenched to room temperature G) quenched in cold water to 380°C in 0.1 second, then held at 380°C for 100 seconds, then quenched to room temperature Necessary Steel Phase Diagram Calculations (continued on p. 6 if necessary): 302 Chapter 10/Phase Tranformations in Metals t 10.02. Tural alor diagram for ally steel (ype 4340) A. austen, lie P. pearlie: Mart be (Adapted from I Boyer, Edis, Atherof Fathermal Tr and Cooling Tranformation Di Annican Soci ty for Metals, 1977. p 181) d+y 19.14 0,40whic r 730°C di Fez C 6.77 707°C O aradway is 707°C instead of 727°C/ 800 700 600 500 400- 300 200 100- of 1 Electd temperature Mistart M (50%) 10 ·Pesc @6.69 wt.20 C 10⁰ 10 Time (s) 10 10⁰ 1400 1200 1000 800 600 400 200 10⁰ Temperature (°F) Wt.7. C The presence of alloying elements other than carbon (e.g. Cr. Ni, Mo, and W) may cause significant changes in the positions and shapes of the curves in the isothermal transformation diagrams. These include (1) shifting to longer times the nose of the austenite-to-pearlite transformation (and also a proeutectoid phase nose, it For the phase of diagram-related may be observed by comparing Fig of a separate bainite nose. These alterations calculations the art of proeutectoid product, approximate 4340 steel as being 1040 steel except that the evtec toid temp Figures 10.13 10.14, which are isothermal transformation diagrams for carbon and alloy steels, respectively Steels in which carbon is the prime alloying element are termed plain carbon steels, whereas alloy steels contain appreciable concentrations of other elements, including those cited in the preceding paragraph. Chapter 12 tells more about the classification and properties of ferrous alloys almest the same as EXAMPLE PROBLEM 10.1 Using the isothermal transformation diagram for an iron-carbon alloy of eutee toid composition (Figure 10.13), specify the nature of the final microstructure (in terms of microconstituents present and approximate percentages) of a small specimen that has been subjected to the following time-temperature treatments In each case assume that the specimen begins at 760°C (1400°F) and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure Temperature (°C) 1700 1500 1300 1100 900 C- 700 500 14 $ 0 4.5% (T) Cu 20 40 Composition (wt% Cu) L TICU Tu 60 Given the time-temperature transformation diagram on page 5, what would be the phases present for a 4340 steel with no alloying elements? Use the bottom of this page to show any work, including any phase diagram-related calculations (worth 5 pts.). A) cooled in air at 2°C/minute to 650°C, then quenched to room temperature B) quenched in cold water directly to room temperature in 0.1 second C) quenched in cold water directly to room temperature in 0.1 second, then heated to 425°C and held there for 1000 seconds, and finally quenched to room temperature D) quenched in cold water to 650°C in 0.1 second, then held at 650°C for 1000 seconds, then quenched to room temperature E) quenched in cold water to 600°C in 0.1 second, then held at 600°C for 5 seconds, then quenched to 350°C, held at 350°C for 60 seconds, and finally quenched to room temperature F) quenched in cold water to 550°C in 0.1 second, then held at 550°C for 5 seconds, then quenched to room temperature G) quenched in cold water to 380°C in 0.1 second, then held at 380°C for 100 seconds, then quenched to room temperature Necessary Steel Phase Diagram Calculations (continued on p. 6 if necessary): 302 Chapter 10/Phase Tranformations in Metals t 10.02. Tural alor diagram for ally steel (ype 4340) A. austen, lie P. pearlie: Mart be (Adapted from I Boyer, Edis, Atherof Fathermal Tr and Cooling Tranformation Di Annican Soci ty for Metals, 1977. p 181) d+y 19.14 0,40whic r 730°C di Fez C 6.77 707°C O aradway is 707°C instead of 727°C/ 800 700 600 500 400- 300 200 100- of 1 Electd temperature Mistart M (50%) 10 ·Pesc @6.69 wt.20 C 10⁰ 10 Time (s) 10 10⁰ 1400 1200 1000 800 600 400 200 10⁰ Temperature (°F) Wt.7. C The presence of alloying elements other than carbon (e.g. Cr. Ni, Mo, and W) may cause significant changes in the positions and shapes of the curves in the isothermal transformation diagrams. These include (1) shifting to longer times the nose of the austenite-to-pearlite transformation (and also a proeutectoid phase nose, it For the phase of diagram-related may be observed by comparing Fig of a separate bainite nose. These alterations calculations the art of proeutectoid product, approximate 4340 steel as being 1040 steel except that the evtec toid temp Figures 10.13 10.14, which are isothermal transformation diagrams for carbon and alloy steels, respectively Steels in which carbon is the prime alloying element are termed plain carbon steels, whereas alloy steels contain appreciable concentrations of other elements, including those cited in the preceding paragraph. Chapter 12 tells more about the classification and properties of ferrous alloys almest the same as EXAMPLE PROBLEM 10.1 Using the isothermal transformation diagram for an iron-carbon alloy of eutee toid composition (Figure 10.13), specify the nature of the final microstructure (in terms of microconstituents present and approximate percentages) of a small specimen that has been subjected to the following time-temperature treatments In each case assume that the specimen begins at 760°C (1400°F) and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure Temperature (°C) 1700 1500 1300 1100 900 C- 700 500 14 $ 0 4.5% (T) Cu 20 40 Composition (wt% Cu) L TICU Tu 60 Given the time-temperature transformation diagram on page 5, what would be the phases present for a 4340 steel with no alloying elements? Use the bottom of this page to show any work, including any phase diagram-related calculations (worth 5 pts.). A) cooled in air at 2°C/minute to 650°C, then quenched to room temperature B) quenched in cold water directly to room temperature in 0.1 second C) quenched in cold water directly to room temperature in 0.1 second, then heated to 425°C and held there for 1000 seconds, and finally quenched to room temperature D) quenched in cold water to 650°C in 0.1 second, then held at 650°C for 1000 seconds, then quenched to room temperature E) quenched in cold water to 600°C in 0.1 second, then held at 600°C for 5 seconds, then quenched to 350°C, held at 350°C for 60 seconds, and finally quenched to room temperature F) quenched in cold water to 550°C in 0.1 second, then held at 550°C for 5 seconds, then quenched to room temperature G) quenched in cold water to 380°C in 0.1 second, then held at 380°C for 100 seconds, then quenched to room temperature Necessary Steel Phase Diagram Calculations (continued on p. 6 if necessary): 302 Chapter 10/Phase Tranformations in Metals t 10.02. Tural alor diagram for ally steel (ype 4340) A. austen, lie P. pearlie: Mart be (Adapted from I Boyer, Edis, Atherof Fathermal Tr and Cooling Tranformation Di Annican Soci ty for Metals, 1977. p 181) d+y 19.14 0,40whic r 730°C di Fez C 6.77 707°C O aradway is 707°C instead of 727°C/ 800 700 600 500 400- 300 200 100- of 1 Electd temperature Mistart M (50%) 10 ·Pesc @6.69 wt.20 C 10⁰ 10 Time (s) 10 10⁰ 1400 1200 1000 800 600 400 200 10⁰ Temperature (°F) Wt.7. C The presence of alloying elements other than carbon (e.g. Cr. Ni, Mo, and W) may cause significant changes in the positions and shapes of the curves in the isothermal transformation diagrams. These include (1) shifting to longer times the nose of the austenite-to-pearlite transformation (and also a proeutectoid phase nose, it For the phase of diagram-related may be observed by comparing Fig of a separate bainite nose. These alterations calculations the art of proeutectoid product, approximate 4340 steel as being 1040 steel except that the evtec toid temp Figures 10.13 10.14, which are isothermal transformation diagrams for carbon and alloy steels, respectively Steels in which carbon is the prime alloying element are termed plain carbon steels, whereas alloy steels contain appreciable concentrations of other elements, including those cited in the preceding paragraph. Chapter 12 tells more about the classification and properties of ferrous alloys almest the same as EXAMPLE PROBLEM 10.1 Using the isothermal transformation diagram for an iron-carbon alloy of eutee toid composition (Figure 10.13), specify the nature of the final microstructure (in terms of microconstituents present and approximate percentages) of a small specimen that has been subjected to the following time-temperature treatments In each case assume that the specimen begins at 760°C (1400°F) and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure Temperature (°C) 1700 1500 1300 1100 900 C- 700 500 14 $ 0 4.5% (T) Cu 20 40 Composition (wt% Cu) L TICU Tu 60

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Phase without alloying elements will be Austenite a M rapid cooling b M rapid co... View the full answer