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Groove pressing (GP) has been successfully adopted to achieve fine grain size up to 7 ?m in AZ31 magnesium alloy with an initial grain size of 55 ?m. The effect of microstructural evolution and surface features on wettability, corrosion resistance, bioactivity and cell adhesion were investigated with an emphasis to study the influence of deposited phases when the samples were immersed in simulated body fluid (SBF 5 �). The role of microstructure was also evaluated without any surface treatments or coatings on the material. GPed samples exhibit improved hydrophilicity compared to the annealed sample. After immersion in SBF, specimens were characterized using scanning electron microscopy (SEM), energy dispersive X-ray (EDAX) analysis and X-ray diffraction (XRD) methods. More amount of white precipitates composed of hydroxyapatite and magnesium phosphate along with magnesium hydroxide was observed on the surfaces of groove pressed specimens as compared to the annealed specimens with an increase in immersion time in SBF. Corrosion behavior of the samples estimated using potentiodynamic polarization curves indicate good corrosion resistance for GPed samples before and after immersion in SBF. The MTT assay using rat skeletal muscle (L6) cells revealed that both the processed and unprocessed samples are nontoxic and cell adhesion was promising for GPed sample. � 2013 Elsevier B.V. All Rights Reserved.

Thin film CdIn2Te4/CdS solar cells were deposited onto the ITO-coated glass substrate by electron beam evaporation (e-beam) technique, and the the effect of annealing on their structural properties is studied. The annealing was performed under nitrogen atmosphere for 1 h. The manufactured solar cells were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDAX) analysis. Crystallite size (D), inter-planer distance (d) and lattice constant (a) values were calculated for the thin film solar cell from XRD data. Annealed samples display well defined XRD patterns with three diffraction peaks. We observed increased peak intensity in the annealed films. EDAX analysis showed that only CdIn2Te4 is present in absorber layer and CdS is found in the window layer, but no impurity atoms are present the structure. It is observed that surface roughness of the annealed films incresed, according to SEM images. The I–V characteristics show that the current is increased for annealed thin films solar cells. © 2017, Pleiades Publishing, Ltd.

We report on microstructure and magnetotransport behavior of ball milled graphite to investigate the effect of particle size on magnetoresistance (MR) in graphite. The observed results show, large values of resistivity and a negative temperature coefficient of resistivity indicating non-metallic, semiconductor nature of the compacts. As the milling time increases, the resistivity value increase which is attributed to the particle size differences of the samples. Graphite exhibits the positive MR at room temperature as well as at low temperatures (4 K). 600 �C annealed samples exhibit less resistivity compared to as-milled samples due to the grain growth during annealing but show large MR values compared to as-milled sample. � 2013 Elsevier Ltd. All rights reserved.

Ultrafine-grained materials produced by different severe plastic deformation methods show very high strengths but their tensile ductility is often very low. In the present work, we demonstrate an approach for retaining high strength while recovering ductility in a Cu-3 at.% Ag alloy through cold rolling and short-time annealing. X-ray line profile analysis of cold-rolled and annealed samples reveals the development of a heterogeneous solute atom distribution due to the dissolution of nanosized Ag particles in some regions of the matrix. In regions with higher solute (Ag) content, the high dislocation density present following rolling is stabilized, while in other volumes the dislocation density is decreased. High-resolution scanning electron microscopy confirms the presence of regions of varying Ag content in the matrix. Microstructure analysis of the rolled and annealed samples revealed bimodal grain size, dislocation density and solute Ag distributions as well as nanosized Ag precipitation. The as-rolled samples exhibit high tensile strengths of ?600-700 MPa with negligible uniform elongation (?1%). After short-time annealing the strength decreases only slightly to ?550-620 MPa with significant improvement in uniform elongation (from 1 to 10%); this is mainly attributed to the bimodal microstructure. � 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

We present comprehensive studies of dc magnetization, ac susceptibility, and magnetotransport of two sets of La0.85 Sr0.15 CoO3 samples, one exhibits phase separation and the other exhibits spin glass behavior. Our study reveals that the phase separation in La0.85 Sr0.15 CoO3 is neither inherent nor ubiquitous; rather, it is a consequence of preparation condition. It is realized that the low temperature annealed sample exhibits phase separation while the high temperature annealed one shows the characteristic of spin glass behavior. This study shows that the most probable magnetic state of La0.85 Sr0.15 CoO3 is spin glass. � 2009 American Institute of Physics.

In this letter, the spatial dependence of the carrier recombination centers induced in phosphorus-implanted and annealed silicon wafers have been examined. Ultrafast time-resolved reflectivity measurements of a set of phosphorus-implanted annealed silicon wafers (10 16P +/cm 2) as a function of position on the wafer have been carried out, and an x-y map of the carrier lifetime for each of the samples has been obtained. Measurements reveal distinct features of the distribution of carrier recombination centers for the nonannealed and annealed samples between 350°C and 1100°C in an area of 36×36μm 2 with resolution better than 3 μm. The presence of islands of clusters in ion-implanted and annealed samples is also discussed in this letter. © 2002 American Institute of Physics. 81 5 856 858 Cited By :3