Please draw the lines for each scenario in the TTT diagram provided 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 andhomogeneous austenitic structure.(1) Cool rapidly to 700°C (1290°F), hold for 104 s, then quench to room temperature(ii) Reheat the specimen in part (i) to 700°C (1290°F) for 20 h.(iii) Cool rapidly to 400°C (750°F), hold for 20 s, then quench to room temperature(iv) Cool rapidly to 400°C (750°F), hold for 200 s, then quench to room temperature.(v) Rapidly cool to 575°C (1065°F), hold for 20 s, rapidly cool to 350°C (660°F), holdfor 100 s, then quench to room temperature.(vi) Rapidly cool to 250°C (480°F), hold for 100 s, then quench to room temperature inwater. Reheat to 315°C (600°F) for 1 h and slowly cool to room temperature. Temperature (°C)800700600500400300200100010-1AM (start)M (50%)M (90%)1110Eutectoid temperatureM + AI10²Time (s)50%10³10⁰140012001000800600400200105Temperature (°F)

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. (1) Cool rapidly to 700°C (1290°F), hold for 10 s, then quench to room temperature (ii) Reheat the specimen in part (i) to 700°C (1290°F) for 20 h. (iii) Cool rapidly to 400°C (750°F), hold for 20 s, then quench to room temperature

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. (1) Cool rapidly to 700°C (1290°F), hold for 10 s, then quench to room temperature (ii) Reheat the specimen in part (i) to 700°C (1290°F) for 20 h. (iii) Cool rapidly to 400°C (750°F), hold for 20 s, then quench to room temperature

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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11.14), specify the na- nure of the final microstructure (in terms of microconstituents present and approximate percentages of each) 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. (a) Cool rapidly to 700°C (1290°F), hold for 104 s, then quench to room temperature. (b) Reheat the specimen in part a to 700°C (1290°F) for 20 h. (c) Rapidly cool to 600°C (1110°F), hold for 4 s, rapidly cool to 450°C (840°F), hold for 10 s, then quench to room temperature. (d) Cool rapidly to 400°C (750°F), hold for 2 s, then quench to room temperature. (e) Cool rapidly to 400°C (750°F), hold for 20 s, then quench to room temperature. (f) Cool rapidly to 400°C (750°F), hold for 200 s, then quench to room temperature. Rapidly cool to 575°C (1065°F), hold for 20 s, rapidly cool to…
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