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|  MIL-W-50504A (AR)
4. 5.5 Retest.
4.5.5.1 Malleable iron. When one or more tension test specimens
fail to comply with the yield strength or elongation requirements,
the rejected heat treat batch may, at the discretion of-the
contractor, be reheat-treated, in which case the samples shall be
selected in accordance with the hardness test requirements. In the
event a reheat is not deemed necessary, each nose casting of the
heat treat batch shall be tested in accordance with 4.5.2 to
establish the hardest and softest nose castings to be tested in
accordance with 4.5.3. When maximum and minimum hardness values
have been determined by compliance of the tensile test specimens
with the mechanical requirements, these values shall be used as a
basis for accepting or rejecting each nose casting within the heat
treat batch. All castings within the heat treat batch with hardness
values outside the established range shall be rejected.
4.5.5.2 Ductile iron. When the tension test specimen fails to
comply with the yield strength or elongation requirements, the
contractor may elect to reheat-treat and the rejected quantity may
be retested by selection of samples in accordance with the hardness
test requirements. If any specimen is outside hardness limits, the
lot shall be rejected. The hardest and softest sample shall be
tested in accordance with 4.5.3. If one or more tensile specimens
fail to comply with the mechanical properties requirements, the lot
shall be rejected. In the event a reheat is not deemed necessary,
each nose casting of the day's heat treat production shall be tested
in accordance with 4.5.2 to establish the hardest and softest nose
castings to be tested in accordance with 4.5.3. When maximum and
minimum hardness values have been determined by compliance of the
tensile test specimens with the mechanical requirements, these
values shall be used as a basis for accepting `or rejecting each nose
casting within the quantity. All castings within the quantity whose
hardness values fall outside the established range shall be rejected.
4.5.5.3 Malleable iron base castings. When one or more tension
test specimens fail to comply with the yield strength or elongation
requirements, the rejected heat treat batch may at the discretion of
the contractor be reheat-treated, in which case the samples shall be
selected in accordance with the hardness test requirements. In the
event a reheat is not deemed necessary, each base casting of the heat
treat batch shall be hardness tested in accordance with 4.5.2 to
establish the hardest and softest base castings to be tested in
accordance with 4.5.4. When maximum and minimum hardness values have
been determined by compliance of the tensile test specimens with the
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