The evaluation of a free fluid surface in a porous medium has several mathematical applications that are important in industries using molds, particularly in the fluid injection process. The vacuum-assisted resin transfer molding (VARTM) process is a promising technology in the primary composite industry. An accurate computational simulation of the VARTM process would be a cost-effective tool i...

objectives: composite restorations must have tooth-like optical properties namely color and translucency and maintain them for a long time. this study aimed to compare the effect of accelerated artificial aging (aaa) on the translucency of three methacrylate-based composites (filtek z250, filtek z250xt and filtek z350xt) and one silorane-based composite resin (filtek p90). materials and methods...

BACKGROUND To facilitate the easier placement of direct resin composite in deeper cavities, bulk fill composites have been introduced. The Mechanical stability of fillings in stress bearing areas restored with bulk-fill resin composites is still open to question, since long term clinical studies are not available so far. Thus, the objective of the study was to evaluate and compare the microtens...

The main objective of this work is to compare the difference between microwave heating and conventional thermal heating in fabricating carbon/epoxy composites. Two types of epoxy resin systems were used as matrices, LY5052-HY5052 and DGEBA-HY917-DY073. All composite samples were fabricated using resin transfer moulding (RTM) technique. The curing of the LY5052-HY5052-carbon and the DGEBA-HY917-...

BACKGROUND Being able to estimate (predict) the final spectrum of reflectance of a biomaterial, especially when the final color and appearance are fundamental for their clinical success (as is the case of dental resin composites), could be a very useful tool for the industrial development of these type of materials. The main objective of this study was the development of predictive models which...

OBJECTIVES This study evaluated the influence of water on the volumetric dimensional change of six direct placement core build-up materials by using Archimedes' principle. METHODS The effect on dimensional change due to the setting reaction was determined through the use of a silicone oil storage medium. The materials used were two dual-cured resin composites (CoreStore and Build-It FR), two ...

We studied the mechanism of volatile-induced surface porosity formation during the resin transfer molding (RTM) of aerospace composites using a blended benzoxazine/epoxy resin, and identified reduction strategies based on material and processing parameters. The influence of viscosity and pressure on resin volatilization were determined. Then, in situ data was collected during molding using a la...

The resin flow behavior in the vacuum assisted resin infusion molding process (VARI) of foam sandwich composites was studied by both visualization flow experiments and computer simulation. Both experimental and simulation results show that: the distribution medium (DM) leads to a shorter molding filling time in grooved foam sandwich composites via the VARI process, and the mold filling time is ...

Resin composites were first introduced as anterior restorative materials, but are more and more used in posterior teeth, as amalgam replacements. Nowadays the so-called ‘condensable’ composites are frequently used in posterior teeth. These materials are subjected to high values of contact and mastigatory loads, loading rates and sliding distances. In such contact conditions, wear is the major f...

Resin transfer molding of an inorganic polymer binder was successfully demonstrated in the preparation of ceramic fiber reinforced engine exhaust valves. Unfortunately, in the preliminary processing trials, the resulting composite valves were too brittle for in-engine evaluation. To address this limited toughness, the effectiveness of a modified fiber-matrix interface is investigated through th...