During fretting, the removal of material by wear leads to an increase of contact stress in the stick zone. If elastic behaviour is assumed, the boundary between stick and slip zones does not move, wear eventually ceases, and a mode-I singularity of contact pressure is predicted after infinitely many cycles. For real materials, the development of singular stresses must be limited by plastic defo...

Due to the increased number of revision total hip arthroplasties (THAs) to correct pain secondary to fretting from modular hip stems, this study was conducted in an effort to correlate objective findings of serum cobalt (Co) levels, serum chromium (Cr) levels, and/or reactive tissue seen on metal artifact reduction sequence (MARS) magnetic resonance imaging (MRI) with a patient's need for revis...

Experimental cast titanium alloys containing 20 mass% chromium (Ti-20Cr) show preferable mechanical properties and a good corrosion resistance. This study evaluated the fretting corrosion behavior of Ti-20Cr. Ti-20Cr (n = 4) and commercially pure titanium (CP-Ti, n = 6) disk specimens were used. The fretting corrosion test was performed by electrochemical corrosion at 0.3 V in 0.9% saline solut...

Affluent western individuals are increasingly fretting about the carbon dioxide emissions from their lifestyle and energy use but one key issue, having fewer children, is little considered. Nigel Williams reports.

A modular femoral head-neck junction has practical advantages in total hip replacement. Taper fretting and corrosion have so far been an infrequent cause of revision. The role of design and manufacturing variables continues to be debated. Over the past decade several changes in technology and clinical practice might result in an increase in clinically significant taper fretting and corrosion. T...

Fretting experiments were conducted on the (10 0) crystal (cubic) face of a single crystal Ni-base superalloy in two directions, /10 0S and /110S, to study the effect of crystallographic orientation on the fretting response in both partial slip and gross slip regimes. The study involved point contacts using a tungsten carbide (WC) ball with radius 10 mm tested at room temperature. Ball indentat...

Fretting fatigue is a degrading process which responsible for considerable amount of mechanical structure failure every year. In the present study, finite element model proposed to show effect bending moment on flat surface under fretting loading. The results that has major friction stress distribution two solids contact. Finite analysis predicts an increased damage when load applied as pure mo...

The pattern of crying and fretting behavior during the first two years is described for 46 !Kung San infants from a hunter-gatherer society in northwestern Botswana. Despite markedly different caretaking practices predisposing to quieter infants, crying and fretting were significantly greater during the first three months, and a peak pattern was present. Measurement of crying 'intensity' indica...

In this research work, an experimental evaluation was conducted to explore the fretting fatigue life of multilayer Cr–CrN-coated AL7075-T6 alloy specimens with higher adhesion strength to substrate as the coating adhesion strength is one of the most critical issues in magnetron sputtering technique. Physical vapor deposition (PVD) magnetron sputtering technique was used for coating purpose, and...