198 CHAPTER 10 Phase Diagrams: The Road Map to Phases and Structures CHAPTER OUTLINE 10.1 Solutions and Mixtures You Know—Water and Antifreeze 10.1.1 Water-Antifreeze Solution 10.1.2 Composition and Temperature Determine Phases Present 10.2 The Iron-Carbon Phase Diagram 10.2.1 Phase Diagram Regions Important to Processing 10.2.2 A1, A3, and Acm Transformation Boundaries 10.3 Transformations of Different Steel Compositions 10.3.1 UNS G10200 Steel 10.3.2 UNS G10800 Steel 10.3.3 UNS G10950 Steel 10.4 Effect of Cooling Rate on Structure and Properties 10.4.1 Slow to Moderate Cooling—Pearlite 10.4.2 More Rapid Cooling 10.5 Additional Thermal Processing to Improve Properties 10.5.1 Tempering Martensite 10.5.2 Spheroidizing Pearlite