MIL-DTL-83054C
to minimize moisture condensation and pooling on the plate surfaces. At the termination of the test,
there shall be no adhesion of the baffle material :o the metal plates nor shall there be any evidence of
pitting, erosion, corrosion, or bad discoloration as a result of the material contact, as determined by
the following procedures. The basis for the comparison shall be the exposed set of control plates.
a. The surfaces of the plates which were in contact with the material shall be inspected for such
things as discoloration, deposits, and pitting. If any of these conditions exists, the surface of the
plates shall be washed in precipitation naphtha. Deposits determined as urethane materials or
elements there from which can be removed by this process shall be construed as adhesion.
b. If any other marks remain on the surface of the plates after being washed in precipitation naphtha
as specified (see 4.6.20(a)), the surfaces shall be lightly polished with a nonabrasive cloth buff. Any
pits or eroded marks remaining after this process shall be construed to be corrosion. Discoloration
or staining (marks which do not physically affect the surface of the plates and which easily wash off
or buff off) shall not be considered detrimental.
4.6.23 Sunshine test. The baffle material shall be tested for up to 100 hours exposure to the
accelerated weathering produced by a carbon arc lamp in accordance with ASTM-G23. Five samples
(slabs) of material, approximately 8x2x2 inches thick, shall be cut from the upper one-third of the test
section and adjacent to or near the qualification test specimens as specified (see 4.6.5). These five
samples shall be exposed for test periods of 20, 40, 80, and 100 hours of continuous spectral radiation.
Sample slabs shall be positioned such that the radiation source is directed at the top surface. At the end
of each test period, a sample shall be cut into four ½ inch thick slabs, identified, and each slab subjected
to the tension tests specified (see 4.6.5) using as many dumbbell specimens as a sample slab will
provide. All values shall be reported, and the percent loss in tensile strength for a given exposure time
and depth shall be calculated. In addition, the extent and depth of visible discoloration to each sample
slab shall be reported. Test specimens and any unused exposed material shall be forwarded to the
qualifying activity for examination. All details relating to the test condition and equipment used shall be
provided including model numbers, type of carbon arc sources, filters, distance of sample slabs from the
light source, sample (drum) rotation speed, test temperature, and humidity.
4.6.24 Infrared spectrum analysis test. The baffle material shall be characterized (identified} by an
infrared spectrometer using a frustrated multiple internal reflectance (FMIR) technique. The spectrum
shall be of such detail as to clearly distinguish it from a standard polyether foam. A reference polyether
spectrum shall be included for comparison. The following criteria shall be satisfied where applicable:
a. Baseline of the spectrum determined at 5 microns wavelength shall be a minimum of 95%
transmittance.
b. Scan speed shall be such as to obtain optimum resolution.
19
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business