Fatigue is the primary cause of failure of crankshafts in internal combustion engines. The cyclic loading conditions and the stress concentrations in the crank pin fillets are unavoidable, and can result in fatigue failure. The objectives of this study were to compare the fatigue behavior of forged steel and ductile iron crankshafts from a one-cylinder engine as well as to determine if the fati...

Warm mix asphalts (WMA), because of their low production and compact temperatures, may have different behaviors in long term. In the present work, the energy-based criteria along with the 50% reduction in initial stiffness (Nf50%) using four-point bending test under controlled-strain conditions of 1000 microstrain were applied to compare the prepared two warm mix and HMA samples. All these crit...

the aim of this research is to investigate the effect of carbon fiber reinforced polymer (cfrp) composite fabric on monotonic and fatigue behaviors of reinforced concrete beams. to control the failure occurrence, a small notch was induced at the middle span in bottom surface for all of the studied rc specimens. totally 12 beams were tested from which 6 beams tested under monotonic and 6 other t...

AIM To compare cyclic fatigue resistance of two geometrically similar nickel-titanium instruments, used in conditions similar to clinical use in reciprocating and continuous rotary motion. METHODOLOGY Four groups of eighteen instruments each, Reciproc(®) files sizes ISO 25 and 40 (R25 and R40) and Mtwo(®) files sizes ISO 25 and 40 (M25 and M40), were tested in reciprocating and continuous rot...

BACKGROUND In dental clinics, dentition defects are commonly restored with conventional porcelain-fused-to-metal fixed bridges. However, Ni-Cr alloy ceramic fixed bridges are known to have several drawbacks such as marginal coloration of the neck, low casting precision and, most seriously, poor biocompatibility. These problems could be circumvented by using noble metal ceramic bridges; however,...

INTRODUCTION Recent improvements in alloys, kinematics, and concepts have been combined to increase the cyclic fatigue resistance of nickel-titanium (NiTi) instruments. The aim of this study was to compare the cyclic fatigue resistance of new M-Wire reciprocating WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) and Reciproc (VDW GmbH, Munich, Germany) files at 2 levels. METHODS Sixty Rec...

Introduction Endodontic instruments are developed to provide a better cleaning of the root canal system and reduce its risk of fracture. The aim of this study was to evaluate the instrumentation time and cyclic fatigue resistance of WaveOne Gold, ProDesign R and ProDesign Logic files. Methods and Materials Thirty Nickel-titanium (NiTi) rotary instruments were divided into 3 groups (n=10). Pro...

OBJECTIVES This study compared the cyclic fatigue resistance of nickel-titanium (NiTi) files obtained in a conventional test using a simulated canal with a newly developed method that allows the application of constant fatigue load conditions. MATERIALS AND METHODS ProFile and K3 files of #25/.06, #30/.06, and #40/.04 were selected. Two types of testing devices were built to test their fatigu...