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Temperature shock tests are
conducted to determine if materiel can withstand sudden changes in the
temperature of the surrounding atmosphere without experiencing physical damage
or deterioration in performance. As a result of exposure to sudden temperature
changes, operation of the test item may be affected either temporarily or
permanently. Examples of problems that could occur as a result of exposure to
sudden changes in temperature are:
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Shattering
of glass.
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Binding
or slackening of moving parts.
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Separation
of constituents.
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Stiffening
of shock mounts.
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Changes
in electronic components.
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Electronic
or mechanical failures due to rapid water or frost formation.
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Differential
contraction or expansion of dissimilar materials.
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Deformation
or fracture of components.
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Cracking
of surface coatings.
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Leaking
of sealed compartments.
Temperature shock testing is performed using two
thermal chambers set at -35 C and +65 C (-31° F and +149 °F), with a
4-hour minimum soak and a 5-minute maximum transfer time between chambers. A total of
four cycles are conducted through both chambers.
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