IronIron Carbide phase diagram a What is the maximum carbon

Iron-Iron Carbide phase diagram

a) What is the maximum carbon content in Austenite?

b) What is the eutectic temperature of Steel?

c) What constituent of steel always contains 0.77 wt% carbon?

d) What are the relative proportions of constituents in 4140 steel (0.4% C)?

e) What is the purpose of adding alloying elements like nickel, chromium, molybdenum and boron to steels?

>> Part (1).

Maximum Carbon Content in Austenite is 2.11 %

>> Part (2)

Eutectic Temperature is that temperature when a liquid phase is converted into two solid hases or vice versa

Fro, seeing the iron carbon diagram, eutectic temperature = 1148 C

>> Part (3).

As, Cementite only forms when carbon percentage is more than 0.77 %

So, Cementite always contains0.77 wt% Carbon

>> Part (4).

It will depend on the temperature, on which we are analysing the steel.