At thermodynamic equilibrium crystals display some disorder due to the spontaneous generation of lattice defects, as we discuss in the case of lattice vacancies. Other examples of defects are color centers in ionic crystals and radiation damage in nuclear reactors. Understanding the role of dislocations in the mechanical properties of materials represented a great advance. Today, nondestructive materials testing has developed into an important field. Magnetic impurities and the Kondo effect are discussed. During the course of many hundreds, if not thousands. of years, people have gained important and useful experience and have learned rules and recipes for the manufacture, in particular, of things made from metallic materials. At first, mechanical properties and strength under mechanical loads, exclusively dominated people’s interest in materials. For example, it had been discovered early on, how long one should hammer a piece of metal in order for it to gain the optimum hardness for its use as a tool, weapon, ornament, or coin. Only in the nineteenth century was the cold straining and cold-work hardening systematically developed, and at the time it reached an impressively high standard, for example, in the large rolling machines of the steel industry. For a long time, this field of metallic materials was dominated by pure empiricism. The microscopic structure of wrought iron was observed for the first time only in 1863. At the time, these experimental studies were performed by Henry Clifton Sorby[aut]Sorby, Henry Clifton, who was born in a suburb of Sheffield, one of the centers of the English iron and steel industry. As an amateur geologist he was interested in the structure of rocks. After he had polished and subsequently etched his samples of wrought iron, in his light microscope he discovered characteristic structures at the sample surface, which are referred to today as the texture of a metallic sample. About 20 years later, Adolf Martens[aut]Martens, Adolf carried out pioneering research in this field, and he gained high recognition as the founder of texture microscopy and of scientific materials testing in Germany. A prominent milestone in Germany at the time was the establishment of the Kaiser-Wilhelm-Institute for Metals Research in Neubabelsberg near Berlin in the year 1920. During 1934 this Institute was moved to Stuttgart. After the Second World War the latter Institute continued in Stuttgart as the Max Planck Institute for Metals ResearchMax Planck Institute for Metals Research. Similar Institutes were established also in the other industrialized countries. (In 2011 the Institute in Stuttgart was renamed Max Planck Institute for Intelligent Systems). After the many discoveries in the field of electricity and magnetism in the nineteenth century, the electric and the magnetic material properties appeared as important new subjects, which had to be investigated. As we have discussed in Chap. 1 in conjunction with the crash of the two English Comet passenger airplanes, it is always the spectacular events and catastrophes, which impressively demonstrate the need for an almost complete understanding of material properties.

Defects in the Crystal Lattice: Useful or Harmful?

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发表日期：

2025年

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Rudolf P. Huebener

摘要

At thermodynamic equilibrium crystals display some disorder due to the spontaneous generation of lattice defects, as we discuss in the case of lattice vacancies. Other examples of defects are color centers in ionic crystals and radiation damage in nuclear reactors. Understanding the role of dislocations in the mechanical properties of materials represented a great advance. Today, nondestructive materials testing has developed into an important field. Magnetic impurities and the Kondo effect are discussed. During the course of many hundreds, if not thousands. of years, people have gained important and useful experience and have learned rules and recipes for the manufacture, in particular, of things made from metallic materials. At first, mechanical properties and strength under mechanical loads, exclusively dominated people’s interest in materials. For example, it had been discovered early on, how long one should hammer a piece of metal in order for it to gain the optimum hardness for its use as a tool, weapon, ornament, or coin. Only in the nineteenth century was the cold straining and cold-work hardening systematically developed, and at the time it reached an impressively high standard, for example, in the large rolling machines of the steel industry. For a long time, this field of metallic materials was dominated by pure empiricism. The microscopic structure of wrought iron was observed for the first time only in 1863. At the time, these experimental studies were performed by Henry Clifton Sorby[aut]Sorby, Henry Clifton, who was born in a suburb of Sheffield, one of the centers of the English iron and steel industry. As an amateur geologist he was interested in the structure of rocks. After he had polished and subsequently etched his samples of wrought iron, in his light microscope he discovered characteristic structures at the sample surface, which are referred to today as the texture of a metallic sample. About 20 years later, Adolf Martens[aut]Martens, Adolf carried out pioneering research in this field, and he gained high recognition as the founder of texture microscopy and of scientific materials testing in Germany. A prominent milestone in Germany at the time was the establishment of the Kaiser-Wilhelm-Institute for Metals Research in Neubabelsberg near Berlin in the year 1920. During 1934 this Institute was moved to Stuttgart. After the Second World War the latter Institute continued in Stuttgart as the Max Planck Institute for Metals ResearchMax Planck Institute for Metals Research. Similar Institutes were established also in the other industrialized countries. (In 2011 the Institute in Stuttgart was renamed Max Planck Institute for Intelligent Systems). After the many discoveries in the field of electricity and magnetism in the nineteenth century, the electric and the magnetic material properties appeared as important new subjects, which had to be investigated. As we have discussed in Chap. 1 in conjunction with the crash of the two English Comet passenger airplanes, it is always the spectacular events and catastrophes, which impressively demonstrate the need for an almost complete understanding of material properties.