Publisher's Synopsis
Recrystallization is a process by which deformed grains are replaced by a new set of defects-free grains that nucleate and grow until the original grains have been entirely consumed. Recrystallization is usually accompanied by a reduction in the strength and hardness of a material and a simultaneous increase in the ductility. Thus, the process may be introduced as a deliberate step in metals processing or may be an undesirable byproduct of another processing step. The most important industrial uses are the softening of metals previously hardened by cold work, which have lost their ductility, and the control of the grain structure in the final product. Recrystallization has been identified as a process in metallic solids since the "old days" (last part of the nineteenth century), when it was supposed that cold working of a metallic workpiece destroyed its crystallinity and that subsequent heating restored the crystalline nature by a process then naturally coined with the name "recrystallization". Nowadays we would define recrystallization as a process that leads to a change of the crystal orientation (distribution) for the whole polycrystalline specimen, in association with a release of the stored strain energy as could have been induced by preceding cold work: a new microstructure results. Recrystallization restores the properties as they were before the cold deformation. Recrystallization occurs in all types of crystalline materials, so not only in metals. However, metals are the only important class of materials capable of experiencing pronounced plastic deformation at relatively low temperatures (i.e. low with respect to the melting temperatures), which explains that most of the corresponding research has been and is performed on metallic materials. Choosing a proper solvent is the first step of the recrystallization process. After selection of a proper solvent, an impure compound is dissolved in the minimum amount of a hot solvent. Then solution is decolorized with activated charcoal (if needed) and any insoluble material is filtered off. If the crystal formation process occurs too rapidly, impurities may become trapped in the crystals. Slowly cooling of the resulting solution to induce crystallization is the next step. Finally the crystals are collected, washed and dried. Recrystallization in Materials Processing is a compilation of research articles contributed by renowned experts from a range of scientific disciplines, such as materials science, metallurgy and pharmacology. The authors emphasize that the progress in this particular field of scientific research is possible today due to coordinated efforts of many research groups that work in materials science, chemistry, physics, pharmacology, and other sciences. Several properties of metallic materials depend to a large extent on the grain structure of the material microstructure. Properties that are influenced by the grain structure include such important quantities as strength, ductility and resistance to creep deformation. Also the strain rate dependence of the material is influenced by the grain size. One of the most important aspects of the grain microstructure is the presence of grain boundaries. As the grain size is reduced, an increasing amount of grain boundaries will be present in the microstructure. Recognizing the importance of the grain microstructure, great possibilities lie in being able to control and take advantage of designed microstructures in practical applications. Such applications include production of metallic materials of superior strength and the development of functionally graded materials, having different properties in different regions, appropriate for a certain product or application. Being able to control aspects of the grain microstructure can also be vital in miniaturization of products, e.g. in the production of micro-electro-mechanical systems (MEMS) and in biomedical applications. Tailoring material properties is further important as it permits lowered weight of products while maintaining the appropriate weight-to-strength ratios, leading to reduced emissions and less negative environmental impact. Recrystallization is a process by which deformed grains are replaced by a new set of defects-free grains that nucleate and grow until the original grains have been entirely consumed. Recrystallization is usually accompanied by a reduction in the strength and hardness of a material and a simultaneous increase in the ductility. Thus, the process may be introduced as a deliberate step in metals processing or may be an undesirable byproduct of another processing step. The most important industrial uses are the softening of metals previously hardened by cold work, which have lost their ductility, and the control of the grain structure in the final product. Recrystallization has been identified as a process in metallic solids since the "old days" (last part of the nineteenth century), when it was supposed that cold working of a metallic workpiece destroyed its crystallinity and that subsequent heating restored the crystalline nature by a process then naturally coined with the name "recrystallization". Nowadays we would define recrystallization as a process that leads to a change of the crystal orientation (distribution) for the whole polycrystalline specimen, in association with a release of the stored strain energy as could have been induced by preceding cold work: a new microstructure results. Recrystallization restores the properties as they were before the cold deformation. Recrystallization occurs in all types of crystalline materials, so not only in metals. However, metals are the only important class of materials capable of experiencing pronounced plastic deformation at relatively low temperatures (i.e. low with respect to the melting temperatures), which explains that most of the corresponding research has been and is performed on metallic materials. Choosing a proper solvent is the first step of the recrystallization process. After selection of a proper solvent, an impure compound is dissolved in the minimum amount of a hot solvent. Then solution is decolorized with activated charcoal (if needed) and any insoluble material is filtered off. If the crystal formation process occurs too rapidly, impurities may become trapped in the crystals. Slowly cooling of the resulting solution to induce crystallization is the next step. Finally the crystals are collected, washed and dried. Recrystallization in Materials Processing is a compilation of research articles contributed by renowned experts from a range of scientific disciplines, such as materials science, metallurgy and pharmacology. The authors emphasize that the progress in this particular field of scientific research is possible today due to coordinated efforts of many research groups that work in materials science, chemistry, physics, pharmacology, and other sciences. Several properties of metallic materials depend to a large extent on the grain structure of the material microstructure. Properties that are influenced by the grain structure include such important quantities as strength, ductility and resistance to creep deformation. Also the strain rate dependence of the material is influenced by the grain size. One of the most important aspects of the grain microstructure is the presence of grain boundaries. As the grain size is reduced, an increasing amount of grain boundaries will be present in the microstructure. Recognizing the importance of the grain microstructure, great possibilities lie in being able to control and take advantage of designed microstructures in practical applications. Such applications include production of metallic materials of superior strength and the development of functionally graded materials, having different properties in different regions, appropriate for a certain product or application. Being able to control aspects of the grain microstructure can also be vital in miniaturization of products, e.g. in the production of micro-electro-mechanical systems (MEMS) and in biomedical applications. Tailoring material properties is further important as it permits lowered weight of products while maintaining the appropriate weight-to-strength ratios, leading to reduced emissions and less negative environmental impact. Recrystallization is a process by which deformed grains are replaced by a new set of defects-free grains that nucleate and grow until the original grains have been entirely consumed. Recrystallization is usually accompanied by a reduction in the strength and hardness of a material and a simultaneous increase in the ductility. Thus, the process may be introduced as a deliberate step in metals processing or may be an undesirable byproduct of another processing step. The most important industrial uses are the softening of metals previously hardened by cold work, which have lost their ductility, and the control of the grain structure in the final product. Recrystallization has been identified as a process in metallic solids since the "old days" (last part of the nineteenth century), when it was supposed that cold working of a metallic workpiece destroyed its crystallinity and that subsequent heating restored the crystalline nature by a process then naturally coined with the name "recrystallization". Nowadays we would define recrystallization as a process that leads to a change of the crystal orientation (distribution) for the whole polycrystalline specimen, in association with a release of the stored strain energy as could have been induced by preceding cold work: a new microstructure results. Recrystallization restores the properties as they were before the cold deformation. Recrystallization occurs in all types of crystalline materials, so not only in metals. However, metals are the only important class of materials capable of experiencing pronounced plastic deformation at relatively low temperatures (i.e. low with respect to the
