INTRODUCTION C/C composites have been used for aerospace application due to their excellent properties such as low density, high heat resistance in inert gas atmosphere, high specific strength and etc. Since C/C composites have relatively higher fracture resistance than other CMCs, this material can also be used as structural components with high reliability. The fatigue properties are also imp...

The effects of surface modification treatments such as shot peening, ion implantation (carbon and nitrogen), surface lubrication (soft coating), laser gas nitriding and various combinations thereof, on the fretting fatigue resistance of Ti-6Al-4V have been investigated. The best of these surface treatments appears to be shot peening. While ion implantation improves the base metal fretting fatig...

BACKGROUND The purpose of this study was to elucidate relationships between quadriceps and hamstrings voluntary muscle fatigue and upper motor lesion impairments in cerebral palsy in order to gain a better understanding of their contribution to the observed fatigue resistance. METHODS Seventeen ambulatory subjects with cerebral palsy (mean age: 17.0, SD=4.8 years) were recruited. Quantitative...

In ergonomics and biomechanics, muscle fatigue models based on maximum endurance time (MET) models are often used to integrate fatigue effect into ergonomic and biomechanical application. However, due to the empirical principle of those MET models, the disadvantages of this method are: 1) the MET models cannot reveal the muscle physiology background very well; 2) there is no general formation f...

Several key fracture-mechanics parameters associated with the onset of subcritical and critical cracking, specifically the fracture toughness, crack-resistance curve, and fatigue threshold, have recently been reported for the superelastic alloy Nitinol, in the product form of the thin-walled tube that is used to manufacture several biomedical devices, most notably endovascular stents. In this s...

INTRODUCTION This study investigated the fatigue and fracture modes of RaCe and ProTaper rotary instruments. MATERIALS AND METHODS Fatigue resistance was evaluated by rotating the files 30° or 60° and with 2 or 5mm radius of curvature. RaCe taper 06 size 25 and ProTaper F1 files (n=40) were used. The number of rotations to failure was analyzed by two-way ANOVA and independent sample t-test. F...

GLARE (GLAss REinforced) belongs to a family of fibre-metal laminates currently being used as a skin material for the upper and side shells in the forward and rear fuselage body of A380. This composite material consists of thin layers of aluminium sheets and unidirectional prepreg layers of glass fibres embedded into an epoxy based matrix. GLARE demonstrates excellent resistance to fatigue crac...

OBJECTIVE The aim of this study was to compare the cyclic fatigue resistance of two nickel-titanium (NiTi) endodontic instruments from ProTaper and GT series X files. STUDY DESIGN Cyclic fatigue test was realized with instruments from ProTaper: F1 and F3 (Denstply Maillefer, Ballaigues, Switzerland) and GT-X: 20.06 and 30.08 (Dentsply Tulsa Dental, Tulsa, Oklahoma, United States of America). ...

When the thermal stresses induced in a geothermal well’s casing string exceed the yield strength of the casing material, the fatigue behavior of the latter can be defined as low cycle fatigue (LCF). The connection threads in the casing body amplify the local stress distribution and lower LCF resistance. A theoretical approach is presented to evaluate LCF resistance and compared with preliminary...

New stent designs must be tested for fatigue resistance before approval for the medical application. Testing under worst-case loading conditions may lead to fractures. For assessment it is important to detect when or after how much test cycles the first strut fractures occur. The monitoring of the electrical resistance is an online method for fracture detection during the fatigue test. This art...