Question

Which of the following percent of carbon is correct for Eutectoid steel (at 723^oC in Fe3-C diag)?

(a) 0.05%

(b) 0.5%

(c) 0.6%

(d) 0.8%

I got this question in unit test.

The above asked question is from Mold Materials in chapter Molding and Core Sands of Casting-Forming-Welding I

Answer 1

Right choice is (d) 0.8%

To explain I would say: At 723^oC in Fe3C diagram the transformation change takes place. The carbon content at this point is 0.8% and is called as eutectoid steel.