Current Attempt in Progress Using the Animated Figure 10.40, the isothermal transformation diagram for a 0.45 wt% C steel alloy, specify the nature of the final microstructure (in terms of the microconstituents present) of a small specimen that has been subjected to the following temperature treatments. In each case assume that the specimen begins at 845 °C and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure. a) Rapidly cool to 700 degrees C, hold for 100,000 s, then quench to room temperature.

Current Attempt in Progress Using the Animated Figure 10.40, the isothermal transformation diagram for a 0.45 wt% C steel alloy, specify the nature of the final microstructure (in terms of the microconstituents present) of a small specimen that has been subjected to the following temperature treatments. In each case assume that the specimen begins at 845 °C and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure. a) Rapidly cool to 700 degrees C, hold for 100,000 s, then quench to room temperature.

Materials Science And Engineering Properties

1st Edition

ISBN:9781111988609

Author:Charles Gilmore

Publisher:Charles Gilmore

Chapter6: Introduction To Mechanical Properties

Section: Chapter Questions

Problem 6.5P

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Using the isothermal transformation diagram for a 0.45 wt% C steel alloy (Figure 10.40), determine the final microstructure (in terms of just the microconstituents present) AND approximate percentages of the microconstituents that form in a small specimen that has been subjected to the following time-temperature treatments. In each case assume that the specimen begins at 845°C (1550°F), and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure. (a) Rapidly cool to 250°C (480°F), hold for 10^3 s, then quench to room temperature. (b) Rapidly cool to 700°C (1290°F), hold for 30 s, then quench to room temperature. (c) Rapidly cool to 700°C (1290°F), hold at this temperature for 10^5 s, then quench to room temperature. (d) Rapidly cool to 400°C (750°F), hold for 500 s, then quench to room temperature.
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