In this paper the feasibility of fabricating controlled porous skeleton of pure tungsten at low temperature by addition of submicron particles to tungsten powder (surface activated sintering) has been studied and the best parameters for subsequent infiltration of Cu were acquired. The effects of addition of submicron particles and sintering temperature on porous as well as infiltrated samples w...

introduction: failures might occur at metal‒porcelain interfaces as a problem with metal‒ceramic restorations even with the application of airborne-particle abrasion technique. this study was undertaken to evaluate the effect of nd:yag laser treatment on the bond strength of porcelain fused to metal. methods:  twenty-four cylindrical specimens (4 mm in diameter and 4 mm in height) were made of ...

a novel starch/poly (vinyl alcohol)/nano-titanium dioxide (st/pva/nano-tio2) biodegradable nanocomposite film was prepared by homogeneously dispersed tio2 nanoparticles in different ratios of starch/pva-based materials, via a solution casting method. glycerol was used as plasticizer. the mechanical and thermal properties of films were studied using tensile and perforation strength tests and the...

an epoxy resin was modified by silica nanoparticles and cured with an anhydride. the particles with different batches of 12, 20, and 40 nm sizes were each distributed into the epoxy resin ultrasonically. electron microscopy images showed that the silica particles were well dispersed throughout the resin. tensile test results showed that young’s modulus and tensile strength increased with the vo...

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...

in this research, the mechanical properties of seven types of nanofilm with differing amounts of silver and silver-clay particles were studied. the elasticity of modulus, tensile strength, toughness, elongation at break, tear strength and color of nanofilms were compared with those of ordinary ldpe film. results showed that the inclusion of nano particles increased the modulus of elasticity, te...

The characterization of high performance PAN—based carbon fibers is described. The process of conversion of polyacrylonitrile fibers into carbon fibers consists mainly of two sequent steps, namely stabilization and carbonization. The ladder structure consisting of acridone ring (40%), naphthyridine ring (30%) and hydronaphthyridine ring (20%) as shown in Fig.5 was assigned for the chemical stru...

In the present study, the influence of annealing temperature on mechanical properties and the microstructure of a high manganese austenitic steel (Fe-30Mn-4Al-4Si-0.5C) was investigated. X-ray diffractometry, optical and scanning electron microscopy, hardness and tensile tests were used to analyze the relationship between mechanical properties and microstructure after annealing process. The res...