Thekey differencebetween dislocation creep and diffusion creep is that位错蠕变是脱位通过材料的晶体结构的运动,而扩散蠕变是diffusion的休假ancies through crystal lattice occurs.
A deformation in physical chemistry refers to the continuum mechanics transformation of a body from a reference structure to a current structure.
内容
1.Overview and Key Difference
2.什么是位错蠕变
3.What is Diffusion Creep
4.Side by Side Comparison – Dislocation Creep vs Diffusion Creep in Tabular Form
5.概括
什么是位错蠕变?
Dislocation creep is a type ofdeformationmechanism in crystalline materials that involves the movement of dislocations through the crystal lattice of the material. This is the mechanism opposite to that of diffusion creep. The dislocation creep causes the plastic deformation of individual crystals, thus, the material itself.
这种类型的变形对材料的差异应力非常敏感。例如,在非常低的温度下,位错蠕变是大多数晶体材料中的主要变形机制。
Dislocation creep in crystals takes place due to the movement of dislocations throughout the crystal lattice. When a dislocation is moving through the crystal, a part of the crystal tends to shift by one lattice point along a plane (which occurs relative to the rest of the crystal). The plane by which the shifted and unshifted regions are separated is named the slip plane. In order to allow this movement, all the ionic chemical bonds along the slip plane must get broke at once. Further, this bond breaking requires so much energy, in theory, to make it possible to take place the dislocation creep. Assuming that the movement takes place stepwise, the bond breaking is immediately followed by a new bond creating at a low energy level.
Due to the movement of a dislocation stepwise through a crystal lattice, it is possible to create a linear lattice defect between the parts of the crystal lattice. There are two types of dislocation creeps namededge and screw dislocations。在边缘错位蠕变中,晶格形成晶格内的额外原子的边缘。在螺丝位错蠕变中,它形成了一条线,沿着晶格晶格跳到一个晶格点。
什么是扩散蠕变?
Diffusion creep is a type of deformation mechanism in crystalline materials where the diffusion of vacancies through the crystal lattice occurs. This deformation technique causes plastic deformation rather than the brittle failure of the material.
This deformation type is comparatively more sensitive to the temperature than other types of deformations that take place in crystal lattices. Diffusion creep typically takes place at high homologous temperatures. Further, diffusion creep causes the migration of crystalline defects through the crystal lattice in a way that when a crystal is undergoing a greater degree of compression in one direction compared to another direction. There, the migration of the defects occurs towards the crystal faces along the direction of the compression. This causes a net mass transfer that causes the shortening of the crystal in the direction where maximum compression takes place.
通常,晶体在显微镜上并不完美。这是因为该晶格中的某些原子位点被点缺陷,颗粒或空缺所占据。这些空缺可以被认为是可以使用异质相平衡来处理的化学物种。在这种现象中,空缺的数量受晶体中化学杂质数量的影响。由于相邻颗粒的“跳跃”,这些空缺可以通过晶体结构移动。
What is the Difference Between Dislocation Creep and Diffusion Creep?
A deformation in physical chemistry refers to the continuum mechanics transformation of a body from a reference structure to a current structure. The key difference between dislocation creep and diffusion creep is that dislocation creep is the movement of dislocations through the crystal structure of a material whereas diffusion creep is the diffusion of vacancies through crystal lattice occurs.
以下信息图表列出了位错蠕变和扩散蠕变之间的差异,以进行并排比较。
概括– Dislocation Creep vs Diffusion Creep
Dislocation creep and diffusion creep are two types of deformation mechanisms in crystal lattices. The key difference between dislocation creep and diffusion creep is that dislocation creep is the movement of dislocations through the crystal structure of a material, whereas diffusion creep is the diffusion of vacancies through crystal lattice occurs.
Reference:
1.“扩散蠕变。”ScienceDirect主题,Available here。
Image Courtesy:
1.“脱发硬币” - 原始上传者是法国维基百科的弗雷德莫姆。- 用户:ZBISASIMONE从Fr.Wikipedia转移到Commons。通过Commons Wikimedia
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