Micro-scale laser shock peening LSP can potentially be applied to metallic structures in microdevices to improve fatigue and reliability performance. Copper thin films on a single-crystal silicon substrate are treated by using LSP and characterized using techniques of X-ray microdiffraction and electron backscatter diffraction (EBSD). Strain field, dislocation density, and microstructure change...

It is known that the wing scales of the emerald-patched cattleheart butterfly, Parides sesostris, contain gyroid-type photonic crystals, which produce a green structural colour. However, the photonic crystal is not a single crystal that spreads over the entire scale, but it is separated into many small domains with different crystal orientations. As a photonic crystal generally has band gaps at...

It is argued in this paper that there are three distinctive physical situations in which the continuum descriptions of crystal plasticity are conceptually different. They are determined by the properties of the random field of dislocation density. One of the cases corresponds to conventional plasticity theory. In this case the system energy possesses the energy density, and a formula for energy...

The microstructure of melt extracted Ti-44Al-8Nb-0.2W-0.2B-1.5Si fiber were investigated. When the rotation speed increased from 2000 to 2600 r/min, the appearance of the wire was uniform with no Rayleigh-wave default. The structure was mainly composed of fine α₂ (α) phase dendritic crystal and a second phase between dendrite arms and grain boundaries. The precipitated second phases were confir...

Variability of fatigue properties of Nickel-based superalloys induced by microstructure feature uncertainties is investigated. The microstructure at one material point is described by its grain size and orientation features, as well as the volume fraction of the c0 phase. Principal component analysis (PCA) is introduced to reduce the dimensionality of the microstructure feature space. PCA and k...

In this work, how synchrotron radiation techniques can be applied for detecting the microstructure in metallic glass (MG) is studied. The unit cells are the basic structural units in crystals, though it has been suggested that the co-existence of various clusters may be the universal structural feature in MG. Therefore, it is a challenge to detect microstructures of MG even at the short-range s...

An anisotropic nonlinear crystal mechanics model is developed for a class of ductile aluminum alloys, with the intent of relating microscopic features and properties to performance of the alloys deformed at high strain rates that may arise during impact and blast events. A direct numerical simulation of dynamic tensile deformation of an aluminum polycrystal demonstrates a tendency for shear loc...

Constitutive stress-strain relations for transformational deformation are discussed. A crystal which can be in two possible phase states is considered. A phase transformation begins during the deformation after a certain amount of elastic strain. For each fixed level of strain an equilibrium polydomain microstructure is established which corresponds to a minimum in the free energy of the crysta...

In this study, the difference between in-phase (IP) and out-of-phase (OP) thermomechanical fatigue (TMF) cycling from 100 to 750 ◦C has been investigated for the Ni-based single-crystal superalloy MD2. In addition, two different crystal orientations were studied, the 〈001〉 and 〈011〉 orientations respectively. When comparing IP and OP TMF lives, a strain range dependency is found for the 〈001〉 d...