MATS 3011 Lecture Notes - Pearlite, Cementite, Plast
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12:30 pm get to bainite --> heat into pearlite region, but actually get speroidite. B, p, and m aren"t eqbm phasesthey = microstructures: start @ 800 oc austenite. Rapid cool to 250 degrees c @ rate of 550 degrees c/s, hold for 103 s @ 250 oc and quench (cool infinitely fast) to room. T cool to 250 (diagonal line b/c given rate) -> get 50% bainite and 45% martensite when you cool to 250 really wants to be alpha-fe and cementite (but cant b/c not eqbm) -> get 100% bainite: cool to 600 degrees in 1 s and wait 10 s. For c to get to cementite, needs to diffuse by red length scale t varies by sqrtt varies by exponentialso t makes more effect than t. If low t but wait really long timeit coarsens: cool to 630 degrees c in 1 s, wait 10 s, and quench. Matsci page 2: how to form 100% speroidite.
