Fretting fatigue process have many features such as early stage crack initiation at contact edge, very slow crack propagation and fatigue failure after very long life operation. In this paper at first we present fretting fatigue model in high cycle region, which is considering the wear process near contact edge. And then we present fretting fatigue life estimation method in low cycle fatigue re...

In recent years many experimental and numerical studies have been conducted on the fatigue behaviour of CNG storage pressure vessels. The main objective of these studies is to estimate the total fatigue life, which consists of two parts: i) Life till crack nucleation and ii) Crack growth life. Although fatigue evaluation methods for metal cylinders are widely covered in literature including the...

This paper presents low cycle fatigue (LCF) life prediction of a coated and uncoated exhaust manifolds. First Solidworks software was used to model the exhaust manifolds. A thermal barrier coating system was applied on the tubes c of the exhaust manifolds, consists of two-layer systems: a ceramic top coat (TC), made of yttria stabilized zirconia (YSZ), ZrO2-8%Y2O3 and also a metallic bond coat ...

abstract background: although studies have demonstrated significant negative relationships between quality of life (qol), fatigue, and the most common psychological symptoms (depression, anxiety, stress), the main ambiguity of previous studies on qol is in the relative importance of these predictors. also, there is lack of adequate knowledge about the actual contribution of each of them in the ...

conclusions: exercise has significant effect on improving symptoms of multiple sclerosis, and cessation of exercise may cause recurrence of symptoms in the intervention group with a slope similar to that of the control group. therefore, continuous rather than short period exercises have valuable symptomatic and supportive relief effects in patients. results: the results indicated significant ch...

In the present study, the effect of various weight fractions of graphene nanoplatelet (GPL) on flexural fatigue behavior of epoxy polymer has been investigated at room temperature and generally the temperature was monitored on the surface of specimen during each test. The flexural stiffness of grapheme nano-platelet/epoxy nanocomposites at 0.1, 0.25 and 0.5 wt. % as a main effective parameter o...

OBJECTIVE To investigate the longitudinal association between the impact of fatigue and health-related quality of life and to determine if potential confounders distorted this association. DESIGN Baseline, 3-, 6- and 12-week assessments of a randomized clinical trial were used. SETTING Outpatient rehabilitation centre. SUBJECTS Patients with idiopathic Parkinson's disease. METHODS Quali...

Scatter behavior of fatigue life in die-cast AM60B alloy was investigated. For comparison, those in rolled AM60B alloy and die-cast A365-T5 aluminum alloy were also studied. Scatter behavior of pore size was also investigated to discuss dominant factors for fatigue life scatter in die-cast materials. Three-parameter Weibull function was suitable to explain the scatter behavior of both fatigue l...