Discs of an extruded AZ80 magnesium alloy were processed by high-pressure torsion (HPT) using 6.0 GPa up to 10 turns at different temperatures (296 K and 473 K). The disc surfaces and cross-sectional planes were examined before and after processing using scanning electron microscopy (SEM) and Vickers microhardness (Hv). The microhardness results at the surface show differences in the strength o...

The effect of laser cladding on the surface microstructure and corrosion properties of coated/uncoated specimens were investigated. Fe-based alloy coating was produced on 35CrMo steel by laser cladding. The phase composition, microstructure, interface element distribution, microhardness and corrosion resistance of the cladding coating were measured. The results show that the cladding layer is m...

The influence of alloying additions on strengthening of high pressure torsion (HPT) processed alloys was investigated using commercially pure Al (Al-1050 alloy) and five Al-(1-3)Mg-(0-4)Cu alloys (in wt%). Microhardness was measured on cross sections. For Al-1050 the microhardness reaches a peak at an effective strain of about 3 and subsequently decreases. The microhardness of Al-Mg-Cu alloys i...

objective: adequate knowledge about restorative materials particularly flowable composite resins with favorable physical properties like optimal microhardness and resistance to environmental factors is a big concern for many dentists. flowable composites have several applications for fissure sealant therapy and preventive resin restorations (prr) which are common treatments in pediatric dentist...

the aim of this study was to analyze the impact of green tea on dentin erosion.twelve extracted sound human premolars were immersed in coca cola with a ph of 2.8 for 5 minutes. the surface microhardness was measured with a knoop diamond under a load of 50gr/10s. the teeth were immersed in green tea (camellia sinensis) solution for one minute. the microhardness values were measured again and com...

Many variables control the critical current density (Jc ) in BSCCO-2223 composites but not all of them are yet well understood, or even positively identified. One important factor is reported to be the density of the BSCCO filament, as measured by microhardness. Since different deformation processes may be used during fabrication, and each can have a different effect on the final BSCCO core den...

Silver and gold have been used for centuries as antimicrobial agents. The aim of the study was to investigate diametral tensile strength, microhardness, ion release and light transmission of experimental resin composites. Flowable dental composite SDR (Dentsply, United Kingdom) was modified by nanogold, nanosilver and silica addition. The metal ion release, light transmission study, microhardne...

Background: Eggshell (ES) is a rich source of minerals since it contains calcium, phosphorous, magnesium, strontium, and fluoride. This study sought to compare the efficacy of nanohydroxyapatite (NHA) and ES for remineralization of enamel caries-like lesions by pH cycling. Materials and Methods: In this in vitro experimental study, artificial enamel carious lesions were induced in 47 human teet...

The aim of this study was to assess the effect of adding nanoparticles to N1 acrylic resin intended for artificial sclera, in terms of the color stability, microhardness, and flexural strength of the resin. Three hundred samples of N1 acrylic resin were used: 100 samples for color stability and microhardness tests (each test was performed on the opposite side of each sample), and 200 samples fo...

Acrylic resins have been widely used due to their acceptable esthetics and desirable characteristics such as easy handling, good thermal conductivity, low permeability to oral fluids and color stability. Flexible resins were introduced on the market as an alternative to the use of conventional acrylic resins in the construction of complete and partial removable dentures. Although these resins p...