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• March 5, 2017 Create Date
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Material - Transparency -Plastic - Plexiglass 55; Static and Fatigue Strength

Abstract : 
Static tensile and notched tensile, tensile fatigue, crack propagation, 
edge attachment and shear-out tests were made with biaxially stretched 
approx.) Plexiglas 55 supplied by the Svedlow Plastics Co. , Los Angeles, 
Calif. test data resulting from tests at -50, 75 and 195 OF are given 
In tabulations and charts.

OBJECT: 
to determine various physical properties Of Plexiglas 55, biaxial Iy 
stretched approximately 7$, for design information purposes and to provide data 
for the selection of minimum acceptable properties for a procurement specification. 
All stretched test epecimens Vere from a single lot of Plexiglas 55 
stretched and furnished by Svedlov Plastics Company. After stretching the material, 
the vendor subjected it to the game heat cycle as a production F—102A canopy 
panel. NO shrink—back Specimens cut from this sheet and shrunk back gave an 
average etretch percentage Of 66.2. As—cast Plexiglas 55 vas also furnished by 
Svedlow Plastics Company. 
Specimen configurations were as follows: 
Static teneilq tests — The 75%' and 194% 
coupons Ln accordance vith Reference (a); the 
shown in Figure 1 to cause failure to occur at 
often failed at the grips. 
Static optcbeé tensUe tests — These were 
specimens were standard tensile 
—50% specimens vere modified as 
the center, since they otherwise 
made as Shovn in Figures 2 and 3.

TEST PROCEDURAS, 
testä — Refärence (a) vas followed, except that the load rate 
was changed to .02 inch per minute, to more closely approach the estiftLted load 
rate in service. Five specimens were run at each of 3 temperatures: 750F, 1940? 
and -50'F. 
petched tensile teqtä - The same procedure for unnotched tensile 
tests was followed. ren specimerB each Of stretched and as—cast Plexiglas 55 Vere 
tested at 75•F. 
fati•æe test' — A Triplett and fatigue machine was used to 
load the . specimens, at a rate of 15 Cycles per minute. Four points vere obtained 
on an curve at 194%. Five specimens were run at at 7,000 psi for a 
minimum Of 20,000 cycles, and five were run at —50 •p •at 10,000 psi for a 
of 20,000 cycles.