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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
ABS;
an abbreviation for Acrylonitrile-Butadiene-Styrene
Accelerated fatigue test;
a test which applies a cyclic loading schedule, which can
be of varying frequency and / or amplitude, to a machine
or component simulating its loading in service, but at a
higher rate, to determine its safe fatigue life before it
is reached in service.
Alloy;
a mixture of atomic species exhibiting metallic properties
and usually prepared by adding other metals or non-metals
to solvent metal in the liquid state. But may also be formed
from sintered powders or by by intimate mixing by mechanical
means. They may be single or multiple phase where the phases
exist as pure elements, solid solutions or intermetallic
compounds.
Annealing (Steel);
Heating to, and holding at a suitable temperature, followed
by relatively slow cooling. The purpose of annealing may
be to remove residual stresses, to soften the alloy, to improve
machinablility, to improve cold working properties, or to
obtain a desired structure.
'beach marks';
'beach marks' highlight advances of a fatigue crack and
are shown by changing conditions at the crack front of stress
or environment. Hence periods of rest when rainwater etc.
can ingress and highlight them as do changes in load or frequency.
(Image)
Brazing;
a method of joining metal parts together by fusing a layer
of brass or other copper alloy between the adjoining surfaces.
A red heat (700-800°C) is necessary and a flux used
to protect the metal from oxidation.
Cold working;
altering the shape or size of a metal by plastic deformation.
Processes include rolling, drawing, pressing, spinning and
extruding. It is carried out below the recrystallisation
point usually at room temperature. Hardness and tensile strength
are increased with cold working whilst ductility and impact
values are lowered. Cold rolling may significantly improve
surface finish.
Corrosion;
follow this link for an explanation of corrosion.
Corrosion fatigue;
When chemically reactive agents can penetrate
into fatigue cracks they can accelerate crack advancement.
The chemical condition within the crack can be more aggressive
than on the free surface. Even if the metal surface at the
crack tip passivates (forms an inert barrier) the next fatigue
loading can crack the brittle deposit and reactivate the
whole process.
DSC; Differential Scanning Calorimetry
This technique takes advantage of the fact
that whenever a material undergoes a change in physical state,
such as melting or transition from one crystalline form to
another, or whenever it reacts chemically, heat is either
absorbed or liberated. Many such processes can be initiated
simply by raising the temperature of the material.
The instrument determines the enthalpies of these processes by measuring
the differential heat flow required to maintain a sample and an inert reference
at a given temperature, usually in the form of a pre-programmed thermal cycle.
Useful information such as melting points, glass transitions, degree of crystallinity,
presence of impurities etc. can be derived from the data obtained.
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