Question

What is the solubility of α ferrite at 0^oC?

(a) 0.1%

(b) 0.02%

(c) 0.005%

(d) 0.0004%

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I would like to ask this question from Iron and Iron Carbide System topic in portion Constitution of Alloys and Phase Diagrams of Engineering Material & Metallurgy

Answer 1

The correct choice is (c) 0.005%

The explanation: α ferrite is an interstitial solid solution of carbon in a BCC crystal lattice. It has a solubility of 0.02% at 723^oC and decreases to 0.005% at 0^oC.