Welding Inspection & Metallurgy API ICP Self Study Notes

c) 50% coarse pearlite + 25% bainite + 25% martensite: To do this, we will
need to have a three step process. First, cool to a temperature above the
nose of the IT curve and hold until you have converted 50% of the austenite
to coarse pearlite. Second, rapidly cool to a temperature below the nose, but
above the M start temperature, and hold until 50% of the remaining austenite is
converted to bainite (this makes 50% of 50% = 25% bainite). Finally, rapidly
quench through the Mf temperature to completely convert the remaining
austenite to martensite