Briefly describe the simplest heat treatment procedure that would be used in converting a \(0.76 \mathrm{wt} \% \mathrm{C}\) steel from one microstructure to the other, as follows: (a) Spheroidite to tempered martensite (b) Tempered martensite to pearlite (c) Bainite to martensite (d) Martensite to pearlite (e) Pearlite to tempered martensite (f) Tempered martensite to pearlite (g) Bainite to tempered martensite (h) Tempered martensite to spheroidite

#Question# Explain the step-by-step heat treatment procedures to convert a 0.76 wt% C steel from (a) spheroidite to tempered martensite, (b) tempered martensite to pearlite, (c) bainite to martensite, (d) martensite to pearlite, (e) pearlite to tempered martensite, (f) tempered martensite to spheroidite, and (g) bainite to tempered martensite. #Answer# (a) To convert spheroidite to tempered martensite, heat the steel above the A3 line, quench rapidly, and temper between 150-450°C. (b) To convert tempered martensite to pearlite, heat the steel above the A3 line, then cool slowly to room temperature. (c) To convert bainite to martensite, heat the steel above the A3 line, then quench rapidly. (d) To convert martensite to pearlite, heat the steel above the A3 line, then cool slowly to room temperature. (e) To convert pearlite to tempered martensite, heat the steel above the A3 line, quench rapidly, and temper between 150-450°C. (f) To convert tempered martensite to spheroidite, heat the steel above the A3 line, then cool slowly to a temperature between 650-700 °C and hold for a sufficient time. (g) To convert bainite to tempered martensite, heat the steel above the A3 line, quench rapidly, and temper between 150-450°C.