Fig. 17.5 Cooling curves (schematic) of (a) gray cast iron, (b) white cast iron, and (c) mottled cast iron. In addition to the stable and metastable eutectic temperatures, the temperatures at the start of the solidification of the pro-eutetic austenite (T ℓ ) and the end of solidification (T f More

Fig. 17.65 Mottled cast iron. Dark areas are gray cast iron. The rest of the cross section is white cast iron. Etchant: picral. More

Fig. 17.40 Gray cast iron C = 3.18%, Si = 2.5%, P = 0.62%. As cast. Graphite flakes and fine microstructure composed of pearlite and interdendritic areas with steadite. Etchant: picral More

Fig. 17.56 Gray cast iron, as cast. C = 3.25%, Si = 1.82%, P = 0.48%. Pearlite, ferrite, lamellar graphite, and steadite. Hardness: 108 HB. Etchant: picral. More

Fig. 5 Tensile testpiece of gray cast iron presenting brittle fracture More

Fig. 7.11 Microstructure of gray cast iron. The black flakes are graphite, the white areas are ferrite, and the grey areas are pearlite. Source: Ref 7.6 More

Fig. 17.21 Gray cast iron with large graphite flakes. Nonmetallic inclusions can also be observed. Not etched. More

Fig. 17.22 Schematic microstructural evolution of a gray cast iron during solidification superimposed on a thermal analysis curve. Some undercooling below the eutectic temperature is needed for nucleation to start. Eutectic solidification happens essentially at constant temperature More

Fig. 17.23 (a) Lamellar graphite in gray cast iron, subjected to deep etching to completely dissolve the metal matrix. Etchant: nital 10%, 2 h LSEM, SE. (b) Tridimensional reconstruction of lamellar graphite in gray cast iron. Section done by focused ion beam (FIB) and images obtained by SE More

Fig. 17.27 Type VII, Distribution C graphite in a gray cast iron. Not etched. More

Fig. 17.30 Gray cast iron. Example of various size classes flakes (ASTM A247), (a) 3, (b) 2, (c) 4. Not etched. More

Fig. 17.31 Gray cast iron. Examples of flakes of various size classes (ASTM A247) (a) 6 (b) 8. Not etched. More

Fig. 17.34 Gray cast iron with ferrite dendrites. Ferrite is formed due to graphitization during cooling in the solid state. Distribution D graphite. Etchant: picral. More

Fig. 17.35 Gray cast iron with pearlite dendrites. Distribution D graphite. Etchant: picral. More

Fig. 17.36 Gray cast iron. Lamellar graphite. Ferrite and pearlite. The eutectic colonies presented in the sketch of Fig. 17.32 (b) can be seen. Courtesy of J. Sertucha, Azterlan, Centro de Investigacion Metalurgica, Durango, Bizkaia, Spain. More

Fig. 17.37 Gray cast iron. Lamellar graphite. Ferrite and pearlite. The eutectic colonies presented in the sketch of Fig. 17.32 (b) can be seen. Courtesy of J. Sertucha, Azterlan, Centro de Investigacion Metalurgica, Durango, Bizkaia, Spain. More

Fig. 17.38 Gray cast iron with 250 MPa (36 ksi) minimum tensile strength (ASTM A48, Class No. 250B). Graphite flakes and pearlitic matrix. Some small manganese sulfide inclusions (gray particles, at the lower right corner of the image, for instance) that enhance machinability. Etchant: nital More

Fig. 17.39 Ternary eutectic in a hypereutectic gray cast iron C = 3.83%, Si = 2.25%, P = 0.46%. Etchant: sodium picrate. More

Fig. 17.41 Gray cast iron with acicular structure. Graphite flakes in a matrix of bainitic ferrite and retained austenite. ASTM A644 defines as “ausferrite” “a cast iron matrix microstructure, produced by a controlled thermal process, which consists of predominantly acicular ferrite and high More

Fig. 17.42 Gray cast iron with acicular structure. Deviation during heat treatment. Complex carbides (containing Mo) that were not properly dissolved in the austenitization stage of the austempering are visible. Graphite flakes in a matrix of ausferrite (see Fig. 17.41 for ausferrite More