Failure analysis of piano strings

A new interesting paper in  » Engineering Failure Analysis » published on ScienceDirect.com.

This paper studies the failure cause of two types of piano strings. Were taken into consideration bass and acute strings of a grand piano concert broken up. The mechanisms leading to rupture the strings are examined. The critical points studied are : tuning pin, agraffe, compression points, environment, tuner.

Read more at : Failure analysis of piano strings.

Failure of rubber O-ring

A new interesting paper in  » Engineering Failure Analysis » published on ScienceDirect.com.

This paper presents the effects of hydrogen pressure, ambient temperature and pressure cycle pattern on fracture behavior of O-rings moulded from a peroxide-crosslinked EPDM rubber with white reinforcing filler under cyclic exposure to high-pressure hydrogen gas.

Read more at : Failure behavior of rubber O-ring under cyclic exposure to high-pressure hydrogen gas

 

NDT in fiber reinforced composites with the pulsed ultrasonic polar scan

A new paper in « Polymer Testing« .

This study investigates the use of both amplitude and time-of-flight based pulsed ultrasonic polar scan P-UPS as a sophisticated non-destructive damage sensor for fiber reinforced composites. Focus is put on stiffness related damage phenomena, which are in general difficult to monitor nondestructively, and their associated signature in the P-UPS image. This paper brings out the study, read more via Non Destructive damage assesment in fiber reinforced composites with the pulsed ultrasonic polar scan.

2013 un bilan de l’activité du blog Les Experts Analyse Défaillances

Les lutins statisticiens de WordPress.com ont préparé le rapport annuel 2013 de ce blog.

En voici un extrait :

Le Concert Hall de l’Opéra de Sydney peut contenir 2.700 personnes. Ce blog a été vu 12  000 fois en 2013. S’il était un concert à l’Opéra de Sydney, il faudrait environ 4 spectacles pour accueillir tout le monde.

Cliquez ici pour voir le rapport complet.

Failure of a Motor Vessel’s Crankshaft 1968

An interesting paper published in  « Engineering Failure Analysis » :

In July 1968 the Swedish motor vessel “MV Stureholm” traveled from Sweden across the North Atlantic with destination to the American gulf harbours.  About 100 nautical miles north of the peninsula Yucatan the 9,000 HP diesel engine failed as a consequence of fatigue failure of the crankshaft. The ship was disabled and had to be towed to Veracruz, Mexico. The Swedish shipowning company decided to perform a temporary repair in Veracruz by welding the fatigue crack. Back in Sweden the damaged but repaired crankshaft was dismounted from the engine and inspected by surveyors. The result was that a fatigue crack had initiated from a subsurface solidification (hot) crack.

This paper brings out the detail of investigation carried out. Read more at : Failure of a Motor Vessel’s Crankshaft 1968.

Premature cracking of dies for aluminum alloy die casting

Die casting AluminiumAn interesting paper of Bogdan Pawlowski, AGH University of Science and Technologie in Krakow, published in « Archives of Metallurgy and Materials » :

Two identical dies for aluminum alloy die-casting failed prematurely because of a number of parallel cracks on the working surface. These cracks were of a mechanical nature related to incorrect microstructural banding orientation of the die core and related to improper heat treatment. The root cause of premature cracking of dies was improper heat treatment (temper embrittlement).

More at :  http://imim.pl/files/archiwum/Vol4_2013/40.pdf

Stress Distributions in a Single-lap Adhesively Bonded Joint

A new interesting paper in « International Journal of Adhesion and Adhesives«  published on ScienceDirect.com.

Increasing applications of adhesively bonded joints require understanding of the stress distribution along the bond-line and the stresses that are responsible for the joint failure. The effect of boundary conditions on the actual stress distributions of a single-lap adhesively bonded joint was investigated using the three dimensional finite element method. This paper brings out the detail of investigation carried out.

More at : Influence of Boundary Conditions on Stress Distributions in a Single-lap Adhesively Bonded Joint.

Damage mechanism and prevention of heavy-haul railway rail

A new interesting paper in  » Engineering Failure Analysis »  of december 2013 published on ScienceDirect.com.

The objective of this paper was to investigate wear and damage behavior of heavy-haul railway rail.

More at : Investigation on the damage mech………