SPECIFICATION RT-1316 ISSUE 2 Page 3
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4.2 SAMPLING INSTRUCTIONS
4.2.1 Qualification Test Samples
Qualification test samples shall consist of six molded slabs, 6 x 6 x 0.075 ± 0.010 inches
(152 x 152 x 1.9 ± .25 mm), and the number of molded components specified. The molded slabs shall be
fabricated from the same lot of material and shall be subject to the same degree of crosslinking as the molded
components.
4.2.2 Acceptance Test Samples
Acceptance test samples shall consist of specimens cut from a molded slab
6 x 6 x 0.075± 0.010 inches (152 x 152 x 1.9 ± .25 mm), and molded components selected at random in
accordance with MIL-STD-105, Inspection Level S-2, AQL 6.5 percent. The molded slab shall be fabricated
from the same lot of material and shall be subjected to the same degree of crosslinking as the molded
components. A lot of components shall consist of all molded components from the same lot of material,
from the same production run, and offered for inspection at the same time.
4.3 TEST PROCEDURES
4.3.1 Dimensional Recovery
Samples of molded components, as supplied, shall be measured for dimensions in accordance with ASTM D
2671. The samples then shall be conditioned for 10 minutes in a 150 ± 2°C (302 ± 4°F) oven, or equivalent,
cooled to room temperature, and remeasured.
4.3.2 Elastic Memory
A 6 x 1/8-inch (152 x 3.2-mm) specimen cut from a molded slab shall be marked with two parallel gage lines
1 inch (25 mm) apart in the central portion of the specimen. The distance between gage lines shall be
recorded as the original length. A 2-inch (5l-mm) portion of the specimen including both gage lines then
shall be heated for 1 minute in a 150 ± 2°C (302 ± 4°F) oven, or equivalent, removed from the oven, and
stretched within 10 seconds, until the gage lines are 4 inches (102 mm) apart. The extended specimen shall
be cooled to room temperature and released from tension. After 24 hours at room temperature, the distance
between the gage line shall be measured and recorded as the extended length. The portion of the specimen
including both gage lines then shall be reheated for 1 minute in a 150 ± 2°C (302 ± 4°F) oven, or equivalent,
and the distance between gage lines then shall be measured and recorded as the retracted length. Expansion
and retraction shall be calculated as follows:
E = Le - Lo
Lo x 100
R = Le - Lr
Le - Lo x 100
Where: E = Expansion (percent)
R = Retraction (percent)
Lo = Original Length [inches (mm)]
Le = Extended Length [inches (mm)]
Lr = Retracted Length [inches (mm)]