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The main sections of the museum are listed below;
Metal Fatigue
Manufacturing Faults
Bicycle Components
Corrosion
Polymers
Composite Materials
Tools of the trade, some ways to investigate problems;
Photoelasticity
Dye penetrant testing
Glossary
of materials engineering terms
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Glossary of materials engineering terms - 2
Edax, EDS- Energy Dispersive
Analysis
Method of elemental analysis of materials by scanning
backscattered X-rays from high volyage electron bombardment usually
in a Scanning Electron Microscope. Characteristic emission peaks enable
identification of most elements.
Endurance limit (fatigue)
In fatigue testing, the number of cycles which may
be withstood without failure at a particular level of stress.
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ESEM - Environmental Scanning Electron Microscope;
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A ESEM is
capable of operating as a conventional
high-vacuum SEM, or under low-vacuum in ESEM mode for the imaging
of 'wet' and non conductive samples, utilizing the ESEM's special
Secondary Electron Detector. The ESEM can be equipped with a range
of Secondary Electron (SE) and Back Scattered Electron (BSE) detectors.
Though a certain degree of resolution has been compromised, microscopists
are able to investigate specimens in their natural state or under
natural environmental conditions - without the need for conventional
preparation techniques that may produce unwanted artefacts in the
sample. Magnifications up to 50,000 times are possible in such environments.
This performance compares favourably with that from many conventional
scanning electron microscopes. The main attraction is the ability
to image materials without coating or other preparation.
Fast fracture;
when a crack propagates instantaneously at a critical
level of stress. The crack may arrest later but usually does not, especially
if the applied stress level is constant or increases.
Fatigue;
follow this link for
an explanation of fatigue.
Fractography;
an important investigative method in forensic
engineering. The study of fracture surfaces of materials to determine
the nature and origin of product failure, e.g. whether brittle or ductile,
single or multiple origns, association with stress concentrations,
and the nature of crack propagation. Analysis usually starts with macrography,
then micrography, often using scanning electron microscopy.
FTIR - Fourier
Transform-InfraRed Spectroscopy;
This technique is used to examine the chemical
bond types present in a polymer (or other IR-absorbent materials) by
taking advantage of the fact that chemical bonds can be stimulated
to vibrate by IR radiation of particular wavelengths. In doing so,
these bonds absorb energy. The strength of the absorption, and the
wavelength at which it occurs, is characteristic of the presence of
a given bond in the structure. Each different bond type has a characteristic
wavelength at which it is stimulated to vibrate in a number of different
modes e.g. stretching, bending or wagging.
By scanning across the IR radiation spectrum and measuring how much of the
supplied energy is transmitted through the sample at each wavelength, a spectrum
is evolved showing a series of absorbance peaks (areas of low energy transmission),
the position of which is directly related to the nature of the chemical bonds
present in the sample. By examining this pattern of peaks, conclusions can
be drawn about the structure and identity of the sample, often by reference
to correlation charts or spectral libraries.
HAZ - Heateffected zone ;
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Whenever welding, brazing and soldering is used
to join metals the neighbouring parent material is effected. It may
be remelted, recrystallised, annealed or stress-relieved due to the
energy input. Material properties such as hardness and yield strength
can be changed (usually reduced) in this region. Low energy and concentrated
heat sources minimise the extent of the zone, such as electron beam
or laser welding compared to gas torch processes.
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