Concept maps steels

Figure 1.13 Portion of a concept map for the processing of a steel alloy found in Chapter 10.

The concept of a sohd solution was also discussed. One form of solid solution in an iron-carbon alloy, or steel (martensite), derives its high strength and hardness from the formation of an interstitial solid solution (carbon dissolved in iron). The following concept map represents this relationship ... 

With a knowledge of the characteristics of dislocation defects, we are able to understand the mechanisms by which metals [i.e., iron-carbon alloys (steels)] permanently deform (Chapter 7), and, in addition, techniques that are used to improve the mechanical properties of these materials. The following concept map notes this relationship ... 

In the design of heat treatments to be used for introducing impurities into semiconductors (i.e., doping. Chapter 18) and, in the production of steel alloys (Chapter 10), an understanding of the temperature dependence of the diffusion coefficient (i.e.. Equation 5.8) is essential. The following concept maps illustrate the preceding relationships for these two materials. 

In this chapter, we defined and explained the types of deformation that metal alloys experience (elastic and plastic) as well as the associated properties (modulus of elasticity, yield strength, hardness, etc.). In order to improve the mechanical characteristics of metal alloys [e.g., steel (Chapter 10)], it is first necessary to understand what these properties represent. The following concept map illustrates this relationship for these materials. 

Other heat treatments are designed to recrystalhze metal alloys that have been strain hardened, to render them softer and more ductile and to develop more desirable grain structures. Two such treatments are described in Section 11.7—process armeahng and, for steels, normalizing. The preceding relationships are indicated in the following concept map. 

For iron-carbon alloys (i.e., steels), an understanding of microstructures that develop during relatively slow rates of cooling (i.e., pearlite and a proeutectoid phase) is facilitated by the iron-iron carbide phase diagram. Other concepts in this chapter were presented as a prelude to the introduction of this diagram—the concepts of a phase, phase equilibrium, metastability, and the eutectoid reaction. In Chapter 10, we explore other microstructures that form when iron-carbon alloys are cooled from elevated temperatures at more rapid rates. These concepts are summarized in the following concept map ... 

Processing/Structure/Properties/Performance correlations and summary concept maps for four materials (steels, glass-ceramics, polymer fibers, and silicon semiconductors), which integrate important concepts from chapter to chapter... 

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