Steels_ Metallurgy and Applications, Third Edition

Low-carbon strip steels 75

.:_ ............. _.. , ~ : ................

I ~ I 2.5wt% Mn I I

/ /%.17wt%c i ~ i '~~ s' I

,ooo ,o--o! f,.o~ "~1

r ''0

/ / -" s ~"=~, o.oewt,/, = = =0 cl I ~." 6 .Y- I .OWl , =,..o, 70 ,,_ MII! g.'.P'~..o..-o I ~_;r lf ''~ o.1 I I

f I o'- I I

600 o~

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200 "** r" i, .r

700 800 900 800 900 800 900

Annealing temperature (~

Figure 1.81 Effect of annealing temperature and chemical composition on the yield
(closed circles) and tensile strength (open circles) of gas jet-cooled steel (After Okamoto
et al. l~)

0.5 1 3 10

Time (rain)

Figure 1.82 Variation of volume per cent of second phase with time of annealing at
775~ (After Sudo and Kokubo 135)

0.5 1 3 5 10

Time (rain)

Figure 1.83 Variation of yieM point elongation with annealing time for a 0.06 wt% C,
1.23 wt% Mn Steel for different annealing temperatures (After Sudo and Kokubo 13s)