grain boundary

简明释义

晶界

英英释义

例句

1.In polycrystalline materials, the grain boundaries 晶界 play a crucial role in determining mechanical strength.

在多晶材料中，晶界 grain boundaries对决定机械强度起着至关重要的作用。

2.The study of grain boundaries 晶界 is essential for understanding material failure mechanisms.

研究晶界 grain boundaries对于理解材料失效机制至关重要。

3.The properties of metals can be significantly affected by the presence of a grain boundary 晶界.

金属的性质可以受到晶界 grain boundary的显著影响。

4.Reducing the size of grain boundaries 晶界 can improve the toughness of ceramics.

减少晶界 grain boundaries的尺寸可以提高陶瓷的韧性。

5.Electrons can be scattered at the grain boundary 晶界, affecting electrical conductivity.

电子在晶界 grain boundary处散射，影响电导率。

作文

The study of materials science has revealed numerous fascinating phenomena that govern the behavior of different substances. One such phenomenon is the presence of grain boundaries, which are critical interfaces between individual crystalline grains in a material. These grain boundaries play a significant role in determining the mechanical, electrical, and thermal properties of materials. Understanding grain boundaries is essential for engineers and scientists who aim to develop stronger and more efficient materials for various applications.To grasp the concept of grain boundaries, it is important to first understand what grains are. In crystalline materials, the structure is composed of ordered arrangements of atoms, forming a repeating pattern known as a crystal lattice. However, in real-world materials, these lattices do not always align perfectly. Instead, they can form regions of varying orientations, which leads to the creation of grains. Each grain is a single crystal with a uniform orientation, while the grain boundaries are the areas where these differently oriented grains meet.The characteristics of grain boundaries can significantly influence the properties of a material. For instance, the strength of metals can be enhanced by refining their grain size. Smaller grains lead to more grain boundaries, which can impede the movement of dislocations—defects within the crystal structure that facilitate deformation. This phenomenon is described by the Hall-Petch relationship, which states that smaller grain sizes result in higher yield strength. Therefore, controlling the size and distribution of grains in a metal can improve its mechanical performance.Moreover, grain boundaries can also affect the electrical conductivity of materials. In semiconductors, for example, the presence of grain boundaries can create barriers for electron flow, leading to variations in conductivity. This behavior is crucial in the design of electronic devices, where the performance can be significantly impacted by the arrangement and characteristics of grain boundaries.In addition to mechanical and electrical properties, grain boundaries also play a vital role in the diffusion processes within materials. At elevated temperatures, atoms can migrate along grain boundaries more easily than through the grains themselves. This increased diffusivity can have implications for processes such as sintering, where powdered materials are compacted and heated to form dense solids. Understanding how grain boundaries influence diffusion can help optimize manufacturing processes and improve the performance of final products.Research into grain boundaries continues to evolve, with advancements in microscopy and computational modeling providing deeper insights into their structure and behavior. Scientists are now able to visualize grain boundaries at the atomic level, revealing their complex nature and how they interact with other defects in the material. This knowledge is paving the way for the development of innovative materials with tailored properties, which could revolutionize industries ranging from aerospace to electronics.In conclusion, grain boundaries are more than just simple interfaces; they are critical features that influence a material's overall performance. By studying and manipulating these boundaries, researchers and engineers can unlock new possibilities in material design, leading to stronger, more efficient, and more reliable products. As our understanding of grain boundaries deepens, the potential for advancements in technology and industry will continue to grow, highlighting the importance of this fundamental concept in materials science.

材料科学的研究揭示了许多迷人的现象，这些现象支配着不同物质的行为。其中一个现象是存在晶界，它们是材料中单个晶粒之间的关键界面。这些晶界在决定材料的机械、电气和热性能方面发挥着重要作用。理解晶界对工程师和科学家来说至关重要，他们旨在开发更强大和更高效的材料，以用于各种应用。要理解晶界的概念，首先需要了解什么是晶粒。在晶体材料中，结构由原子的有序排列组成，形成一种称为晶格的重复模式。然而，在现实世界的材料中，这些晶格并不总是完全对齐。相反，它们可以形成方向不同的区域，从而导致晶粒的形成。每个晶粒都是具有均匀取向的单一晶体，而晶界则是这些方向不同的晶粒相遇的区域。晶界的特性可以显著影响材料的性能。例如，金属的强度可以通过细化其晶粒尺寸来增强。较小的晶粒导致更多的晶界，这些晶界可以阻碍位错的运动——晶体结构中的缺陷，促进变形。这种现象被称为霍尔-佩奇关系，该关系指出，较小的晶粒尺寸会导致更高的屈服强度。因此，控制金属中晶粒的大小和分布可以改善其机械性能。此外，晶界还可以影响材料的电导率。例如，在半导体中，晶界的存在可能会为电子流动创造障碍，导致电导率的变化。这种行为在电子设备的设计中至关重要，因为性能可能会受到晶界的排列和特性的显著影响。除了机械和电气性能外，晶界在材料内部的扩散过程中也发挥着重要作用。在高温下，原子可以沿着晶界比通过晶粒本身更容易地迁移。这种扩散率的增加可能对烧结过程产生影响，在该过程中，粉末材料被压实并加热以形成致密固体。了解晶界如何影响扩散可以帮助优化制造工艺并提高最终产品的性能。对晶界的研究不断发展，显微镜技术和计算建模的进步提供了对其结构和行为的更深入见解。科学家们现在能够在原子水平上可视化晶界，揭示其复杂的性质以及它们与材料中其他缺陷的相互作用。这些知识为开发具有定制性能的创新材料铺平了道路，这可能会彻底改变航空航天、电子等行业。总之，晶界不仅仅是简单的界面；它们是影响材料整体性能的关键特征。通过研究和操控这些边界，研究人员和工程师可以解锁材料设计的新可能性，导致更强大、更高效和更可靠的产品。随着我们对晶界理解的加深，技术和工业进步的潜力将继续增长，突显了这一材料科学基本概念的重要性。