In the paper, we study mechanical behavior of a three-dimensional chiral metamaterial using numerical modeling. A feature structures is that during their uniaxial loading twisting observed along axis. rod composed 3 × 9 unit cells corresponding three orthogonal axes. The relative strain compression sample in simulation did not exceed 3.3%. was performed by finite element method threedimensional...

the development of nano/ultrafine bainitic structure in aisi 52100 steel was the goal of this study. for this purpose,the aisi 52100 the specimens were austenitized at 1050 °c for 60 min followed by low-temperature austemperingtreatment at different temperatures and times. the austempered samples were characterized using field emissionscanning electron microscopy (fesem), x-ray diffraction (xrd...

in this paper, a new method is proposed for the production of mwcnts/pvc (multi-walled carbon nanotubes/ polyvinyl chloride) nanocomposites. in this method, a spray is used to produce layers of carbon nanotubes within a pvc matrix. various parameters influence the production of the nanocomposite and its mechanical properties. these parameters are studied separately and the effect of each of par...

nanocomposites based on polyamide 6/polypropylene  )pa6/pp 67/33) blend containing 2.5 to 10 phr of nano-caco3  and 5 phr of maleated polypropylene )pp-g-mah) as compatibilizer were prepared by melt compounding followed by injection molding. the mechanical properties, water absorption, as well as shrinkage behavior were characterized and the morphology was studied using scanning electron micros...

nanoclay/triphenyl phosphate hybrid system was employed to examine the fire retardancy and mechanical properties of pc/abs blends. each of the polymers and their blends are widely used in the automotive, electrical andelectronic industries. because most thermoplastics are easily combustible they need to be flame retarded to reduce the burning rate especially in the initial phase of a fire incid...

this work investigates the feasibility of using recycled high density polyethylene (rhdpe), recycled polypropylene (rpp) and old newsprint fiber (onp) to manufacture fiber reinforced composites. the boards were made through air-forming and hot press. the effects of the fiber loading and coupling agent content on tensile, flexural, internal bond properties and water absorption and thickness swel...

the aim of this study was to evaluate sound and decayed wood of iranianbeech (fagus orientalis) with a nondestructive stress wave method. wood samples,with dimensions of 9 by 19 by 200 mm were decayed in laboratory soil-bed tests,based on european pre-standard env-807. the decay was evaluated by measuringbending dynamic modulus of elasticity (moed) and longitudinal dynamicmodulus of elasticity ...

in order to improve particle properties, new processes combining granulation and crystallization are being developed. this work deals with the spherical crystallization process by the quasi-emulsion mechanism applied to carbamazepine, a pharmaceutical drug. the aim of the present study was to produce of spherical grains made of mall crystals of a drug that have adequate properties for direct co...

  There are many factors such as voltages, duty cycle, pressure, temperatures and gas flux in coatings process that were effective in changing coatings characteristic. In this paper in plasma enhanced chemical vapor deposition (PECVD) technique, temperature and gas flux are two important variants that affecting the coatings structure and mechanical properties. All TiC coating deposited on a hot...