Optical sensing and imaging applications often suffer from a combination of low resolution object reconstructions and a large number of sensors which, depending on frequency, can be quite expensive or bulky. It is therefore desirable to minimize the number of sensors (which reduces cost) for a given target resolution level (image quality) and permissible total sensor array size (compactness). E...

Powder metallurgy (P/M) technique is usually used for manufacturing porous metal materials. However, some P/M materials are limitedly used in engineering for their performance deficiency. A novel 304 stainless steel P/M material was produced by a solid-state sintering of 304 stainless steel powders and 304 short stainless steel fibers, which were alternately laid in layers according to mass rat...

This paper reports the results of an experimental work conducted to investigate the effect of curing conditions on the compressive strength of self-compacting geopolymer concrete prepared by using fly ash as base material and combination of sodium hydroxide and sodium silicate as alkaline activator. The experiments were conducted by varying the curing time and curing temperature in the range of...

Regardless of the excellent properties of glass ionomer cements, their poor mechanical properties limit their applications to non-load bearing areas. This study aimed to investigate the effect of incorporated short, chopped and randomly distributed flax fibers (0, 0.5, 1, 2.5, 5 and 25 wt%) on setting reaction kinetics, and mechanical and morphological properties of glass ionomer cements. Addit...

Thermal stability, structure and mechanical properties of the multi-component Zr58.5Ti8.2Cu14.2Ni11.4Al7.7 bulk metallic glass have been studied in detail. The glassy material displays good thermal stability against crystallization and a fairly large supercooled liquid region of 52 K. During heating, the alloy transforms into a metastable icosahedral quasicrystalline phase in the first stage of...

Thin films bonded to compliant substrates often develop wrinkles when subjected to an applied or inherent compressive stress. This paper presents a bilayer model to account for surface effects on the wrinkling of ultrathin solid films. Assuming a surface layer of finite thickness, effects of surface properties on the critical strain, the equilibrium wavelength, and the wrinkle amplitude are dis...

Bioactive glass (BG) is widely used for bone tissue engineering. However, poor mechanical properties are the major shortcomings. In the study, hydroxyapatite nanowhisker (HANw) was used as a reinforcement to improve the mechanical properties. 63s glass/HANw scaffolds were successfully fabricated by selective laser sintering (SLS). It was found that the optimal compressive strength and fracture ...

in this paper, the effect on the strength properties of high strength concrete (hsc) manufactured with silica fume (sf) and ground pumice (gp) is investigated. portland cement was replaced with sf, gp and combination of sf and gp up to 25%. 22 different concrete mixtures with these replacement ratios were produced by using 0.25 water-binder ratio. the ultrasound pulse velocity, compressive, spl...

In compressive fracture of dry plexiform bone, we examine the individual roles of overall mean porosity, the connectivity of the porosity network, and the elastic as well as the failure properties of the nonporous matrix, using a random spring network model (RSNM). Porosity network structure is shown to reduce the compressive strength by up to 30%. However, the load-bearing capacity increases w...

The effects of the residual stress (either compressive or tensile) induced during the heat-treatment process on the electrical properties of Pb(Zr0.52Ti0.48)O3 (PZT) films were investigated. The PZT films were deposited on platinized silicon substrates by the rf-magnetron sputtering method using a single oxide target. After their deposition, the films were bent elastically by means of a special...