polyvinyl ester green composites were synthesized with walnut shell powder (wsp) by in-situ polymerization technique. the green composites have been evaluated for mechanical properties such as tensile strength, tensile modulus and hardness. sliding wear loss, specific wear rate and coefficient of friction were investigated by using computerized pin-on–disc machine at normal applied loads of 20,...

This study investigated the true stress (σ)–true strain (ε) relationship up to plastic deformation limit in ferrite–pearlite (FP) steel at various temperatures. We found that a decrease temperature resulted an increase lower yield strength (LYS) and tensile (TS), both uniform total elongations. When was increased from 673 773 K, TS elongations decreased due blue brittleness. In σ–ε of FP temper...

background and aims. polymethyl methacrylate, pmma, is widely used in prosthodontics for fabrication of removable prostheses. this study was undertaken to investigate the effect of adding silver nanoparticles (agnps) to pmma at 2% and 0.2% concentrations on compressive and tensile strengths of pmma. materials and methods. the silver nanoparticles were mixed with heat-cured acrylic resin in an a...

background and aims. although microwave irradiation has been used for disinfection of dental stone casts, there are concerns regarding mechanical damage to casts during the process. the aim of this study was to evaluate the effect of microwave irradiation on the compressive strength (cs) and diametral tensile strength (dts) of stone casts. materials and methods. in this in vitro study, 80 cylin...

in this paper, hardness and tensile properties of welded zone of aluminum 1100 alloys by friction stir welding process was investigated and the effects of rotational and traverse speeds of tool on these parameters was studied. also the fracture cross-section of welded samples was investigated. according the results of this paper, the hardness of weld material is higher than base material and is...

the incorporation of boehmite nano-particles and its effects on the mechanical properties and bond strength of an experimental dental adhesive were studied.an adhesive solution containing ethanol, bis-gma, tmptma, hema and photo-initiator system (camphorquinone and dmaema) was prepared. silanized boehmite nano-particles were incorporated into the adhesive in different concentrations of 0, 0.2, ...

in this research, the influence of adding micro- and nano- sized calcium carbonate powders to nylon-66 was investigated. mechanical properties of micro and nano- composites, including tensile strength, elongation, and young’s modulus, before and after ageing, were determined and analyzed. for this purpose, micro- and nano-sized caco3 particles were used as fillers to prepare micro-composites (c...

It is commonly proposed that the fatigue strength can be enhanced by increasing the tensile strength, but this conclusion needs to be reconsidered according to our study. Here a recrystallized α-Cu-15at.%Al alloy with moderate grain size of 0.62 μm was fabricated by cold rolling and annealing, and this alloy achieved exceptional high fatigue strength of 280 MPa at 10(7) cycles. This value is mu...

Using molecular dynamics we find that the tensile strength of the contacts between two clean platinum surfaces with nanoscale asperities is strongly size dependent with a maximum strength for contact lengths of approximately 5 nm. This is the first time a strongest size is observed in single crystals. The strengthening with decreasing size down to 5 nm results from a decrease in the initial den...

A three-dimensional (3D) representative volume element (RVE) model was developed for analyzing effective mechanical behavior of fiber-reinforced ceramic matrix composites with imperfect interfaces. In the model, the fiber is assumed to be perfectly elastic until its tensile strength, and the ceramic material is modeled by an elasto-plastic Drucker-Prager constitutive law. The RVE model is then ...