A preliminary report by the inquiry team found the most likely cause of the April 29 tragedy near Bergen was a fatigue fracture
in a second stage planet gear.
This test shows that the fatigue fracture
of lead-free solder joints under the thermal cycling test is creep fracture, where the crack initiation always occurs in external edges of solders.
The magnitude, frequency, and rate of exposure make the bones less able to store energy, potentially resulting in fatigue fracture
. The type of fracture--i.e., cross-sectional, longitudinal oblique, spiral, etc.--depends on the magnitude and velocity of the load and direction of load application.
The investigators are calling this failure mode "Cu lead fatigue fracture
." Other issues stem from the higher elastic modulus of the quartz-filled alternatives, which leads to more package stress.
The character of the fatigue fracture
of the specimens was observed by the electron scanning microscope at the Faculty of Mechanical Engineering at the University of Zilina.
The probability of crack detection during inspection and monitoring is generally evaluated in an intermediate stage, and subsequently linked to the (calculated) probability of fatigue fracture
to obtain the probability of failure according Sustainable Bridges: 2006:
The volume's 15 chapters address component design, overview of the mechanisms of failure in heat treated steel components, mechanisms and causes of failure in heat treated steel parts, general aspects of failure analysis, failure in steel forging, failures from the casting process, sources of failures in carburized and carbonitrided components, fatigue fracture
of nitrided layers, steel heat treatment failures due to quenching, steel failures due to tempering and isothermal heat treatment, failure analysis in tool steels, case studies of steel components failures in aerospace applications, failure analysis of powder metal steel components, induction hardening, and failure analysis of steel welds.
LEG INJURY: Sharpeyed Albert Park officials noticed that the statue of Brian Clough had a serious fatigue fracture
on its supporting leg and had become unstable Picture by Peter Reimann
The specimen was cyclically loaded until a substantial fatigue fracture
The midfielder suf-fered a fatigue fracture
to his right foot during last week's memorable victory over AC Milan in Istanbul.