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This is due to a decrease in stress concentration of grain boundary junctions and also due to the stress distribution of 5-7 defects along the grain boundary where the compressive and tensile stress are produced by the pentagon and heptagon rings, etc. Chen at al. [19] have done research on the inverse HallPetch relations of high-entropy ...
In materials science, a grain boundary is the interface between two grains, or crystallites, in a polycrystalline material. Grain boundaries are two-dimensional defects in the crystal structure, and tend to decrease the electrical and thermal conductivity of the material.
However, little attention has been given to slip bands within grains (i.e., in the absence of grain boundary interaction). The long-range stress field (i.e., the elastic strain field) around the tip of a stress concentrator, such as a slip band, can be considered a singularity equivalent to that of a crack.
This toughening becomes noticeable when there is a narrow size distribution of particles that are appropriately sized. Researchers typically accept the findings of Faber's analysis, which suggest that deflection effects in materials with roughly equiaxial grains may increase the fracture toughness by about twice the grain boundary value.
In metallurgy, materials science and structural geology, subgrain rotation recrystallization is recognized as an important mechanism for dynamic recrystallisation.It involves the rotation of initially low-angle sub-grain boundaries until the mismatch between the crystal lattices across the boundary is sufficient for them to be regarded as grain boundaries.
Grain boundary sliding (GBS) is a material deformation mechanism where grains slide against each other. This occurs in polycrystalline material under external stress at high homologous temperature (above ~0.4 [1]) and low strain rate and is intertwined with creep.
Stress fields can be created by adding different sized atoms to the lattice (solute strengthening). If a smaller atom is added to the lattice, a tensile stress field is created. The atomic bonds are longer due to the smaller radius of the solute atom. Similarly, if a larger atom is added to the lattice, a compressive stress field is created.
The strength of materials is determined using various methods of calculating the stresses and strains in structural members, such as beams, columns, and shafts. The methods employed to predict the response of a structure under loading and its susceptibility to various failure modes takes into account the properties of the materials such as its yield strength, ultimate strength, Young's modulus ...