WebIt is now recognized that grain boundary sliding (GBS) is often an important mode of deformation in polycrystalline materials. This paper reviews the developments in … 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 ) and low strain rate and is intertwined with creep. Homologous temperature describes the operating … See more Rachinger sliding is purely elastic; the grains retain most of their original shape. The internal stress will build up as grains slide until the stress balances out with the external applied stress. For example, when a uniaxial … See more When polycrystalline grains slide relative to each other, there must be simultaneous mechanisms that allow for this sliding to occur without the overlapping of grains (which would be … See more Grain boundary scattering has been observed experimentally using various microscopy techniques. It was first observed in NaCl and MgO bicrystals in 1962 by Adams … See more Grain shape plays a large role in determining the sliding rate and extent. Thus, by controlling the grain size and shape, the amount … See more Lifshitz sliding only occurs with Nabarro–Herring and Coble creep. The sliding motion is accommodated by the diffusion of … See more The total strain under creep conditions can be denoted as εt , where: εt = εg + εgbs +εdc εg = Strain … See more Nano-crystalline materials, or nanomaterials, have fine grains which helps suppress lattice creep. This is beneficial for … See more
Grain Boundary Softening from Stress Assisted Helium
WebGrain boundary sliding is a process in which grains slide past each other along, or in a zone immediately adjacent to, their common boundary (Langdon and Vastava 1982). Adams and Murray (1962) first observed … WebJan 1, 2024 · Superplasticity effect appears in materials with grain size less than 10μm, and at specific temperature and stain rate [2, 3], where grain boundary sliding is generally considered as the main deformation mechanism. Nevertheless, superplasticity was also found in TiAl [4], Ni-45Al [5] with large grain sizes (far larger than10μm). manitowoc auto repair
Diffusion creep - Wikipedia
WebJan 15, 2024 · Grain boundary sliding 1. Introduction Dynamic recrystallization (DRX) is a recrystallization phenomenon occurring concurrently during deformation [1]. DRX has been observed mostly in face-centered cubic (FCC) metals and alloys having low or medium stacking fault energies (SFE) [2]. WebJul 1, 1972 · Grain boundary sliding can be conveniently studied by loading helical springs wound of wire with a “bamboo” structure. Such tests on pure silver coils show that identically-stressed boundaries slide at widely different rates, and that the sliding rate in any one boundary is very anisotropic. WebSegregation of rare earth alloying elements are known to segregate to grain boundaries in Mg and suppress grain boundary sliding via strong chemical bonds. Segregation of Mn, however, has recently been found to enhance grain boundary sliding in Mg, thereby boosting its ductility. Taking the Mg (2¯114) twin boundary as an example, we … kory langhofer az