People with narrow minds fail to recognize that the definition of Impossible is 'lack of initiative and incentive' – Serena Butler

Problem 9.55 Compute fractions of proeutectoid ferrite and pearlite for Fe-0.25C alloy. Why was this problem assigned? Understand the terms proeutectoid ferrite and pearlite Learn to use the equilibrium Fe-C diagram See that diagram tells amounts of microconstituents The concept is important; resulting nos. are not (as far as course is concerned)

Problem 9.55 Compute fractions of proeutectoid ferrite and pearlite for Fe-0.25C alloy. Gives proeut. FE fraction: (0.77-0.25)/0.75 = 0.69

Problem 9.55 Compute fractions of proeutectoid ferrite and pearlite proeut. FE fraction = 0 proeut. FE fraction = 0.25 proeut. FE fraction = 1

Problem 9.57 Total FE = 0.9, total CM = 0.1. Hypo or hyper? Why was this problem assigned? Use the terms hypoeutectoid, hypereutectoid Total FE, total CM? (where's the beef?) More contact with Fe-C diagram

Problem 9.57 Total FE = 0.9, total CM = 0.1. Hypo or hyper? Total FE = 0.9 = (6.67-x)/6.65 x = 0.68

Problem 10.14 Use TTT curves predict microstructures when steel is cooled as specified Why was this problem assigned? Understand TTT curves Connect cooling process with microstructure Recognize variety of microstructures possible

Problem 10.14 Use TTT curves predict microstructures when steel is cooled as specified Essentially all P

Problem 10.14 Use TTT curves predict microstructures when steel is cooled as specified Roughly 2/3 bainite + 1/3 MAR

Problem 10.14 Use TTT curves predict microstructures when steel is cooled as specified Roughly 2/3 bainite + 1/3 MAR