Three different laminated composites are used in this study: carbon fiber, woven glass and glass-fiber-reinforced epoxy. The composite laminate structures were fabricated using the hand lay-up technique at room temperature. laminates reinforced with epoxy resin, fibers (CFRP), (GFRP-W), random-orientation (GFRP-R) to obtain eight layers. wear test was performed a pin-on-disc tribometer five loa...

abstract statement of the problem: surface roughness is a key factor in the aesthetics of restorative dentistry as it can determine the clinical quality and success of restorative materials. the chemical process of dissolution in the presence of mechanical forces can accelerate the surface roughness of tooth-coloured restorative materials. objectives: to determine the degree of surface roughnes...

St. Croix White hair sheep ewes were used to evaluate the effect of supplemental nutrition prior to breeding during the dry and wet seasons on St. Croix. Beginning 21 d prior to breeding ewes were fed supplement in addition to grazing guineagrass pasture (FEED). Other ewes in the flock grazed pasture only (CONTROL). This study was conducted during the dry (June and July) and wet seasons (Octobe...

background: this study was conducted to assess the effect of thickness and hydration condition on the surface microhardness of endosequence root repair material putty (errm; brasseler usa, savannah, ga), a premixed bioceramic material. materials and methods: polymethyl methacrylate cylindrical molds with an internal diameter of 4 mm and three heights of 2, 4, and 6 mm were fabricated. in group ...

Thisin vitro study was conducted to evaluate the effect of tooth whitening on the surface roughness of dental restorative materials using AFM. Two hybrid resin composites and nano-ionomer were fabricated in samples with 2 mm thickness and 6 mm diameter. No changes in roughness was observed for all three materials tested after 14 days of bleaching with 20% carbamide peroxide (CP), compared to th...

PURPOSE This study investigated the influence of sealant application on stain resistance of a nanohybrid resin composite compared to the efficacy of a bonding agent used as a surface sealant on prolonging color stability of the resin composite. MATERIALS AND METHODS 28 disc-shaped materials were prepared from a nano-hybrid resin composite Filtek Z550 and assigned to four groups: G1K: nonseale...

The most common fillers for syntactic foam development are glass microballoons or fly ash cenospheres. However, the need improved properties and reduced cost requires exploring other possibilities. In this work, foams of vinyl ester resin reinforced with expanded particles (EG) were fabricated compressive composites studied. EGS was smaller size 0.04–0.125 mm in 15, 30, 45 vol.% EGL had larger ...

AIM This study aimed to compare the solubility of a universal restorative resin composite (Filtek Z250; FZ250) and a silorane-based resin composite (Filtek Silorane; FS) after immersion in alcohol-containing mouthrinse, alcohol-free mouthrinse, and artificial saliva. METHODS 30 discs (10 mm × 1 mm) were prepared from each material and desiccated until a constant mass was obtained. Specimens w...

The HEPHAISTOS system integrates advantageously the basic processing steps as tooling, tempering of the resin and lay up, the impregnation of the fibers, pre-forming techniques as well as finally the process curing of the composite structures. Composites for aerospace applications in prepreg and wet technology have been successfully fabricated and investigated for quality and certification issu...

In this research, creation of higher mechanical natural fiber mat composites was proposed. The hybrid mat with jute and glass mat was fabricated by needle punching system, in which jute mat was placed on glass mat. The ratio of jute and glass mat layers was set to be 1:0,1:1,1:2 and 2:1, respectively. The composites were fabricated by hand-lay up method with unsaturated polyester resin after ne...