Particulate Metal Matrix Composites (PMMCs) have attracted interest for application in numerous fields. The current processing methods often produce agglomerated particles in the ductile matrix and as a result these composites exhibit extremely low ductility. The key idea to solve the current problem is to adopt a novel Rheo-process allowing the application of sufficient shear stress (τ) on particulate clusters embedded in liquid metal to overcome the average cohesive force or the tensile strength of the cluster. In this study, cast A356/SiC p composites were produced using a conventional stir casting technique and a novel Rheo-process.The microstructure and properties were evaluated. The adopted Rheo-process significantly improved the distribution of the reinforcement in the matrix. A good combination of improved Ultimate Tensile Strength (UTS) and tensile elongation (ε) is obtained.

In this Letter we demonstrate a polarization controller capable of changing any state of polarization of light from one arbitrary state to another. The controller consists of a stack of three homogeneous nematic liquid-crystal cells. The polarization state is controlled by proper adjustment of the voltages applied across each of the cells. The mathematical algorithm and principles of this polarization controller are developed in the framework of the Stokes parameters, allowing easy visualization by use of a Poincaré sphere representation. The transformation functions are given for conversion of an arbitrary input state to any output state. Experiments are carried out to demonstrate arbitrary polarization transformation.

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A variety of chiral esters of a range 4-n-alkanoyloxybiphenyl-4'-carboxylic acids have been prepared in order to produce three closely related homologous series of liquid-crystalline materials. The majority of the materials synthesized were found to exhibit smectic liquid-crystalline phases close to room temperature. Many of these phases were also found to be ferroelectric. Moreover, the ferroelectric behaviour observed was found to be very unusual, and in the case of some materials a peculiar change in sign of the spontaneous polarization direction with temperature was detected.

In this letter we demonstrate an inverse twisted nematic device in which the input polarized light is unaffected in the field-off state and produces a polarization rotation in the field-on state. This is done by using a homeotropically aligned sample containing chiral nematic liquid crystal with negative dielectric anisotropy and specially prepared surfaces.