Results 11 to 20 of about 1,476 (257)
Length-scale effect due to periodic variation of geometrically necessary dislocation densities
International Journal of Plasticity, 2013 Abstract Strain gradient plasticity theories have been successful in predicting qualitative aspects of the length scale effect, most notably the increase in yield strength and hardness as the size of the deforming volume decreases. However new experimental methodologies enabled by recent developments of high spatial resolution diffraction methods in ...
Oeztop, Muin S. +2 more
openaire +4 more sources
Viewpoint: experimental recovery of geometrically necessary dislocation density in polycrystals
Scripta Materialia, 2003 Abstract Application of electron backscattering diffraction methods to recover estimates of the geometrically necessary dislocation density is described. The limitations of the method arising from the opacity of crystalline materials and the spatial and angular resolution limits are discussed.
B.S El-Dasher, B.L Adams, A.D Rollett
openaire +4 more sources
Resolving geometrically necessary dislocation density onto individual dislocation types using EBSD-based continuum dislocation microscopy [PDF]
International Journal of Plasticity, 2016 Abstract Modeling of plasticity is often hampered by the difficulty in accurately characterizing dislocation density on the microscale for real samples. It is particularly difficult to resolve measured dislocation content onto individual dislocation types at the length scales most commonly of interest in plasticity studies.
T.J. Ruggles, D.T. Fullwood, J.W. Kysar
openaire +1 more source
Evolution of geometrically necessary dislocation density from computational dislocation dynamics
IOP Conference Series: Materials Science and Engineering, 2009 This paper presents a method for calculating GND densities in dislocation dynamics simulations. Evolution of suitably defined averages of GND density as well as maps showing the spatial nonuniform distribution of GNDs are analyzed under uniaxial loading.
P J Guruprasad, A A Benzerga
openaire +1 more source
Microhardness model based on geometrically necessary dislocations for heterogeneous material
Journal of Materials Research and Technology, 2021 Lamellar cast irons are known as heterogeneous materials. Their overall hardness is determined by the microhardness of their microstructure contents. This study pertains to extend the indentation size effect (ISE) analyses to these heterogeneous materials.
Mohammed Mendas +3 more
openaire +2 more sources
Metals, 2022 Gradient nano-grained (GNG) metals have shown high synergetic strength and good ductility due to their unique gradient microstructure. In this study, the mechanical behavior of gradient nano-grained metals was investigated by three-dimensional discrete ...
Songjiang Lu +4 more
doaj +1 more source
Size-dependent geometrically necessary dislocation structures in single-crystalline tungsten
Journal of Materials Research, 2022 Abstract Wedge indentation experiments were conducted to study the depth dependence of geometrically necessary dislocation (GND) structures in single-crystalline tungsten. Single-crystalline tungsten exhibits a pronounced indentation size effect (ISE), which can be rationalized based on GNDs. The dislocation mechanisms,
Jin Wang +4 more
openaire +5 more sources
The role of geometrically necessary dislocations in giving material strengthening [PDF]
Scripta Materialia, 2003 The role of geometrically necessary dislocations in providing macroscopic strengthening is reviewed with particle reinforcement as an examp le. The general relation between the Nye tensor and slipalong a curvilinear slipline net is derived to emphasise the importance of curvature of slip lines upon the rate of dislocation storage.
N.A Fleck, M.F Ashby, J.W Hutchinson
openaire +1 more source
Materials Research Letters, 2019 This paper reports on a heterogeneous-structured β-Ti alloy with an exceptional combination of high strength and ductility, resulting from optimized hierarchical features in a lamellar microstructure.
Sumin Shin +3 more
doaj +1 more source
Journal of Materials Research and Technology, 2023 It is urgent to explore an efficient treatment strategy to obtain characteristic microstructures for better mechanical properties of alloys in an era of energy shortage.
Yafei Wang +3 more
doaj +1 more source