(Solved): Using the Animated Figure 10.22, the isothermal transformation diagram for an alloy of eutectoid c ...

Using the Animated Figure 10.22, the isothermal transformation diagram for an alloy of eutectoid composition, specify the nature 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 temperature treatments. In each case assume that the specimen begins at \( 760^{\circ} \mathrm{C} \) and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure. (a) Rapidly cool to 600 degrees C, hold for 4 s, rapidly cool to 450 degrees \( C \), hold for \( 10 \mathrm{~s} \), then quench to room temperature. (b) Rapidly cool to 700 degrees \( \mathrm{C} \), hold for \( 10,000 \mathrm{~s} \), heat to 760 degrees \( \mathrm{C} \), hold for \( 1 \mathrm{~h} \), then quench to room temperature.