(2005) Fracture behavior of polyetherimide (PEI) and interlaminar fracture of CF/PEI laminates at elevated temperatures. Abstract To investigate effects of environmental temperature on fracture behaviour of a polyetherimide (PEI) thermoplastic polymer and its carbon fibre (CF/PEI) composite, experimental and numerical studies were performed on compact tension (CT) and double cantilever beam (DC...

This study investigated the residual tensile properties of plain woven jute fiber reinforced poly(lactic acid) (PLA) during thermal cycling. Temperature ranges of thermal cycling tests were 35-45 °C and 35-55 °C. The maximum number of cycles was 10³ cycles. The quasi-static tensile tests of jute fiber, PLA, and composite were conducted after thermal cycling tests. Thermal mechanical analyses of...

The present article focuses on changes in the mechanical properties of an all-oxide fiber-reinforced composite following long-term exposure (1000 h) at temperatures of 1000–1200°C in air. The composite of interest derives its damage tolerance from a highly porous matrix, precluding the need for an interphase at the fiber–matrix boundary. The key issue involves the stability of the porosity agai...

This paper demonstrates the viability of in-situ transmission electron microscopy for studying the deformation mechanisms of polymer nano-composites. In-situ straining studies are performed on carbon multiwalled nanotube (MWNT)-polystyrene composite films. The experiments show that load transfer across the nanotube-polystyrene interface is operative well into the plastic deformation regime of t...

We studied whether obturing canals and restoring endodontic occlusal access cavities on upper premolars could provide acceptable resistance and pattern to fracture. Eighteen upper premolars were divided equally into 3 groups. Group 1 consisted of intact controls; group 2 had access cavities and root canal preparations; group 3 as in group 2 but obturated with gutta-percha and AH26, and the acce...

This study evaluated the repair bond strength of a nanohybrid resin composite to a novel CAD/CAM hybrid ceramic based on four intraoral ceramic repair systems. Vita Enamic (VE) CAD/CAM hybrid ceramic was used in this study. Specimens were divided into five test groups according to the repair method performed on the ceramic surface: Gr C (No treatment; control); Gr CZ (Cimara Zircon); Gr PR (Por...

BACKGROUND This study compared two well-known computer-aided-design/computer-aided-manufactured (CAD/CAM) blocks (Paradigm MZ100 [3M ESPE] and Vitablocs Mark II [Vita] in terms of fracture toughness (Kic), index of brittleness (BI) and stress/strain distributions. MATERIAL AND METHODS Three-point bending test was used to calculate the fracture toughness, and the relationship between the Kic a...

OBJECTIVES The aim of the present investigation was to study the influence of a reduced bone support on the fracture resistance of endodontically treated teeth restored with glass fibre-reinforced posts (FRC). METHODS 30 caries-free maxillary central incisors were divided into 3 groups (n=10). Endodontic treatment was performed. Teeth were flattened 2 mm above the cemento-enamel junction. Gro...

nowadays, textile and woven fabric composites are taken into consideration forapplications in high mechanical properties and every in-plane direction. however, developments inmodelling and characterisation of the fabric reinforced composite materials are considered more inthe effects of element types used in the mesh generation of the crack tip. the type of elementselected for the crack tip, a ...

this report describes a case of an eight years old girl who was treated for complicated crown fracture of right maxillary central incisor because of a sport accident. for the tooth total pulpotomy was performed in order to achieve apexogenesis and the tooth was restored with a composite resin. the patient was reviewed over 10 years. at first the tooth showed continued root development and compl...