A liquid crystal blazed grating having a prismatic polymer microstructure has been developed. The polymer structure is fabricated by photo-induced localization and polymerization of a small concentration of monomer onto one substrate of an electro-optical cell by using ultraviolet light irradiation at the direction 45 degrees from normal incident. Using this method a periodical one-dimensional ...

To improve the material characteristics of singleand poly-crystals of pure copper, the respective relationships between crystallographic orientations and microstructures, and the bending and mechanical properties were examined. And texture distribution is also analyzed. A grain refinement procedure was performed to obtain a grained structure. Furthermore, some analytical results related to crys...

The permeability k and porosity φ of vesicular basalts are measured. The relationship between k and φ reflects the formation and emplacement of the basalts and can be related to the crystal and vesicle microstructure obtained by image analysis. Standard theoretical models relating k and φ that work well for granular materials are unsuccessful for vesicular rocks due to the fundamental differenc...

Low-cost magnesium aluminate spinel ceramics were successfully synthesized from the minerals of magnesite(M) and bauxite(B) via one-step sintering method. The effect ratio bauxite to magnesite on phase evolution, microstructure, as well mechanical properties was thoroughly investigated. structural analysis indicated that Mg2+ or Al3+ ions dissolved in lattice formed Mg-rich/Al-rich MgAl2O4 (MA)...

Microstructural control of CaO–Al2O3–SiO2 (CAS) glass-ceramics (GCs) bearing metastable CaAl2Si2O8, a layered crystal, from parent glass having single composition was achieved by increasing the amounts WO3 and carbon used as sources metallic W particle nucleation agents. The average crystal size increased 9.3 to 49 µm when amount were fivefold in preparation CAS GCs. To investigate effect separ...

We perform atomistic Monte Carlo simulations of bending a Lennard-Jones single crystal in two dimensions. Dislocations nucleate only at the free surface as there are no sources in the interior of the sample. When dislocations reach sufficient density, they spontaneously coalesce to nucleate grain boundaries, and the resulting microstructure depends strongly on the initial crystal orientation of...

OBJECTIVES The primary aim of this research was to investigate the wear behavior and wear mechanism of five different veneering porcelains. METHODS Five kinds of veneering porcelains were selected in this research. The surface microhardness of all the samples was measured with a microhardness tester. Wear tests were performed on a ball-on-flat PLINT fretting wear machine, with lubrication of ...

Oriented attachment has created a great debate about the description of crystal growth throughout the last decade. This aggregation-based model has successfully described biomineralization processes as well as forms of inorganic crystal growth, which could not be explained by classical crystal growth theory. Understanding the nanoparticle growth is essential since physical properties, such as t...

Numerous experimental studies have shown that evolution of the martensite microstructure in shape memory alloys can lead to plastic deformation. This results in poor functional fatigue in many commercial applications, whereby strain incrementally advances with repeated thermal cycling under stress. This can also affect structural fatigue, whereby repeated cycling initiates and grows fatigue cra...