OBJECTIVES To evaluate the effect of cyclic loading on the bond strength of resin composite to zirconia framework material. METHODS Bar shaped zirconia/composite specimens (2 mm x 2 mm x 25 mm) were prepared using three different resin cements and placed in a four-point bending test setup. The flexure strength (F(s)) was calculated by placing the bars (n=10) fixed between the four supports (a...

Age-related non-traumatic fractures are a major health problem. Historically, only bone mass was considered to predict fracture risk but other factors, including accumulation of microdamage, may also affect bone quality and contribute to bone fragility. Previous studies conducted in our laboratory have demonstrated that the predisposition of bone to form linear microcracks and not diffuse damag...

In this paper two robust H∞ feedback control laws are designed, one for active wing bending damping, and one for active damping of the wing and hull bending modes. For the latter, not only symmetrically commanded ailerons are used, but also the elevator and direct lift control (DLC) flaps. The control objective of these feedback laws is the reduction of fatigue of the wing roots, as well as the...

BACKGROUND Osseointegrated endosseous implants are widely used for the rehabilitation of completely and partially edentulous patients, being the final prosthodontic treatment more predictable and the failures extremely infrequent. A case of fracture of an endosseous dental implant, replacing the maxillary first molar, occurring in a middle-age woman, 5 years after placement is reported. MATER...

In this paper, the stress intensity factor (SIF) variations along an arbitrarily developing crack front, the non-planar fatigue-crack growth patterns, and the fatigue life of a round bar with an initially straight-fronted surface crack, are studied by employing the 3D symmetric Galerkin boundary element method-finite element method (SGBEM-FEM) alternating method. Different loading cases, involv...

The crankshaft is one of the most critically loaded components as it experiences cyclic loads in the form of bending and torsion during its service life. Its failure will cause serious damage to the engine so it’s important at the time of design to verify fatigue strength. More challenges in crankshaft design due to increasing vehicle payloads, lower weight requirement, higher efficiency and lo...

Fatigue analysis of aluminum-alloy welded joints based on the linear elastic notch-stress approach is presented in this paper. The International Institute Welding proposes two variants approach, one for thick joints, i.e., with a plate thickness 5 mm or more, reference radius rref = 1 mm, using FAT71 design curve, and thin less than 0.05 FAT180 curve. In work, feasibility proposed S–N curves, o...

Fatigue damage accumulation under variable amplitude loadings is vital for the life prediction of welded structures. An approach based on distribution mapping presented. S-N curves joints are utilized to construct fatigue zones, and a corresponding polynomial fitting function derived from heat transfer FEA solution. Experimental results cruciform T tensile three-point bending employed validatio...