ProblemIsothermal transformation diagram for an iron-carbon alloy of eutectoid com-position (0.76 wt% C). Assume that the specimen begins at 760°C and that it has been held at thistemperature long enough to have achieved a complete and homogeneous austenitic structure.Sketch the followingtreatment on the figure: Rapidly coolto 575°C, hold for 20s, rapidly cool to350°C, hold for 100s, then quench toroom temperature. Specify microcon-tituents with percentage.1.Sketch the followingtreatment on the figure: rapidly cool to600°C, hold 4s, rapidly cool to 450°C,hold for 108, and rapidly cool to roomtemperature. Specify microcontituentswith percentage.3. (Sketch the followingtreatment on the figure: rapidly cool to450°C, hold 10s, rapidly cool to roomtemperature, heat to 680°C, hold 30hrs,and cool to room temperature. Specifymicrocontituents with percentage.Temperature (°C)4.(a) 0.2 wt% C with spheroidite(b) 0.2 wt% C with fine pearlite800(c) 0.76 wt% C with fine pearlite(d) 0.76 wt% C with tempered martensite70060050040030020010010-1AAAM(start)M(50%)M(90%)1Rank from the highest to the lowest hardness:10M+A-Eutectoid temperaturePB50%10² 10³Time (s)104105

Problem Isothermal transformation diagram for an iron-carbon alloy of eutectoid com- position (0.76 wt% C). Assume that the specimen begins at 760°C and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure. 1. Sketch the following treatment on the figure: Rapidly cool to 575°C, hold for 20s, rapidly cool to 350°C, hold for 100s, then quench to room temperature. Specify microcon- tituents with percentage. 2. Sketch the following treatment on the figure: rapidly cool to 600°C, hold 4s, rapidly cool to 450°C, hold for 10s, and rapidly cool to room temperature. Specify microcontituents with percentage. 3. Sketch the following treatment on the figure: rapidly cool to 450°C, hold 10s, rapidly cool to room temperature, heat to 680°C, hold 30hrs, and cool to room temperature. Specify microcontituents with percentage. Temperature (°C) 4. (a) 0.2 wt% C with spheroidite (b) 0.2 wt% C with fine pearlite (e) 0.76 wt% C with fine pearlite (d) 0.76 wt% C with tempered martensite 800 700 600 500 400 300 200 100 10-1 M(start) M(50%) M(90%) Rank from the highest to the lowest hardness: 10 M+A -Eutectoid temperature P 10² Time (s) B 50% 10³ 104 105

Problem Isothermal transformation diagram for an iron-carbon alloy of eutectoid com- position (0.76 wt% C). Assume that the specimen begins at 760°C and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenitic structure. 1. Sketch the following treatment on the figure: Rapidly cool to 575°C, hold for 20s, rapidly cool to 350°C, hold for 100s, then quench to room temperature. Specify microcon- tituents with percentage. 2. Sketch the following treatment on the figure: rapidly cool to 600°C, hold 4s, rapidly cool to 450°C, hold for 10s, and rapidly cool to room temperature. Specify microcontituents with percentage. 3. Sketch the following treatment on the figure: rapidly cool to 450°C, hold 10s, rapidly cool to room temperature, heat to 680°C, hold 30hrs, and cool to room temperature. Specify microcontituents with percentage. Temperature (°C) 4. (a) 0.2 wt% C with spheroidite (b) 0.2 wt% C with fine pearlite (e) 0.76 wt% C with fine pearlite (d) 0.76 wt% C with tempered martensite 800 700 600 500 400 300 200 100 10-1 M(start) M(50%) M(90%) Rank from the highest to the lowest hardness: 10 M+A -Eutectoid temperature P 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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