The isothermal transformation diagram for and iron- carbon alloy of eutectoid composition is given in figure. 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 time-temperature treatments. In each case, assume that the specimen begins at 760°C. Show your work on the diagram. a. Cool rapidly to 300°C, hold for 5 s. b. Cool rapidly to 600°C hold for 100 s, then quench to room temperature. C. Cool rapidly to 500°C, hold for 7 s, and then quench to room temperature. Temperature (°C) 800 700 600 500 400 300 200 100 0 10 A A A M(start) M(50%) M(90%) 1 1 10 M-A Eutectoid temperature 10² Time (s) B 50% 10³ 104 105

The isothermal transformation diagram for and iron- carbon alloy of eutectoid composition is given in figure. 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 time-temperature treatments. In each case, assume that the specimen begins at 760°C. Show your work on the diagram. a. Cool rapidly to 300°C, hold for 5 s. b. Cool rapidly to 600°C hold for 100 s, then quench to room temperature. C. Cool rapidly to 500°C, hold for 7 s, and then quench to room temperature. Temperature (°C) 800 700 600 500 400 300 200 100 0 10 A A A M(start) M(50%) M(90%) 1 1 10 M-A Eutectoid temperature 10² Time (s) B 50% 10³ 104 105

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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