(Solved): Using the isothermal transformation diagram for an iron-carbon alloy of eutectoid composition, spec ...

Using the isothermal transformation diagram for an iron-carbon alloy of eutectoid composition, specify the nature of the final microstructure of a small specimen that has been subjected to the following time-temperature treatments. In each case assume that the specimen begins at $$760^{?}\mathrm{C}$$ and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure. (a) Cool rapidly to $$700^{?}\mathrm{C}(1290^{?}\mathrm{F}$$ ). hold for $$10^{+}$$s. then quench to room temperature. (b) Reheat the specimen in part (a) to $$700^{?}\mathrm{C}\left(I290^{?}\mathrm{F}\right)$$ for $$20\mathrm{h}$$. (c) Rapidly cool to $$600^{?}\mathrm{C}\left(1110^{?}\mathrm{F}\right)$$, hold for 4 s, rapidly cool to $$450^{?}\mathrm{C}$$ $$\left(840^{?}\mathrm{F}\right)$$. hold for $$10\mathrm{s}$$, then quench to room temperature.