Objective: To evaluate the influence of the surface used for manipulation (paper block and glass slab) on the mechanical properties (flexural strength and elastic modulus) and ion release (F) of two resin modified glass ionomer cements (RMGIC). Methods: Two RMGICs: Vitro Fil LC (DFL) and Riva Light (SDI) were used. The materials were manipulated on two different surfaces: block of paper and gla...

We show that the interaction between flexural phonons, when corrected by the exchange of electron-hole excitations, may drive the graphene sheet into a quantum critical point characterized by the vanishing of the bending rigidity of the membrane. Ripples arise then due to spontaneous symmetry breaking, following a mechanism similar to that responsible for the condensation of the Higgs field in ...

The model of the large deflection of fabrics considering the effect of bending hysteresis was established for describing the post-buckling behavior of woven fabrics. The moment-curvature relationship of fabrics obtained by pure bending test was approximated by the Rate-model and the change in the flexural rigidity caused by the hysteresis was incorporated into the analysis. Using a nonlinear FE...

AIM To evaluate the bending fatigue lifetime of nickel-titanium alloy (NiTi) and stainless steel (SS) endodontic files using finite element analysis. METHODOLOGY The strain-life approach was adopted and two theoretical geometry profiles, the triangular (TR) and the square cross-sections, were considered. Both low-cycle fatigue (LCF) lifetime and high-cycle fatigue (HCF) lifetime were evaluate...

AIM The aim of this in vitro study was to compare the flexural strength, the flexural modulus and compressive strength of the acrylic polymer reinforced with glass, carbon, polyethylene and Kevlar fibres with that of plain unfilled resin. MATERIALS AND METHODS A total of 50 specimens were prepared and divided into 10 specimens each under 5 groups namely group 1- control group without any fibr...

PURPOSE The impact strength and the flexural properties of denture base materials are of importance in predicting their clinical performance upon sudden loading. This study compares the impact and transverse strengths and the flexural modulus of three denture base polymers. MATERIALS AND METHODS The investigation included a relatively new microwave-polymerized polyurethane-based denture mater...

STATEMENT OF THE PROBLEM Composite resin may be used in different temperatures; it is crucial to determine the effect of temperature on mechanical properties of nanohybrid and silorane-based composite. PURPOSE This in vitro study compared the flexural strength and modulus of elasticity of nanohybrid and silorane-based resin composite, at 4˚C, room temperature (25˚C), and 45˚C. MATERIALS AND...

the effect of an electroless ni-cu-p coating on the fatigue behavior of quenched and tempered ck45 steel has been investigated. the fatigue tests under rotating bending conditions have been conducted in three different conditions of uncoated, as-deposited and shot peened prior to the coating deposition. the results indicate that plating of the base steel leads to a fatigue life reduction. the d...

Acoustic emission and transient IR thermography have been used to study and compare the performance of carbon/epoxy laminates, subjected to two different indentation procedures in a three-point flexural rig, one with a supporting steel plate and the other in a free bending mode. The study of 2-D localisation plots and cumulative counts vs. time curves allowed clarifying, with the essential supp...

In this paper, rotating bending fatigue tests of 2024-T4 Al alloy with different oxide coatings were carried out. Compared to the uncoated and previously reported oxide coatings of aluminum alloys, the fatigue strength is able to be enhanced by using a novel oxide coating with sealing pore technology. These results indicate that the better the coating surface quality is, the more excellent the ...