Page 203 - Materials Chemistry, Second Edition

190 3 Metals

Figure 3.22. Time-temperature-transformation (TTT) diagrams for (a) austenitic steel, and (b) an alloy
steel (type 4340); A ¼ austenite, B ¼ bainite, P ¼ pearlite, M ¼ martensite, F ¼ proeutectoid ferrite.
Reproduced with permission from Callister, W. D. Materials Science and Engineering: An Introduction,
7th ed., Wiley: New York, 2007. Copyright 2007 John Wiley & Sons, Inc.