Estimate the Brinell hardnesses for specimens of a 0.45 wt% C iron-carbon alloy that have been subjected to the heat treatments described in parts (a), (d), and (h) of Problem 10.20.

(a) Rapidly cool to 250(C (480(F) hold for 103 s, then quench to room temperature.

(d) Rapidly cool to 700(C (1290(F) hold at this temperature for 105 s, then quench to room temperature

(h) Rapidly cool to 625(C (1155(F), hold at this temperature for 10 s, rapidly cool to 400(C (750(F), hold at this temperature for 5 s, then quench to room temperature.