NOTE 7—Test results have shown that for some materials such as glass
cloth, SMC, and BMC laminates, other specimen types should be
considered to ensure breakage within the gage length of the specimen, as
mandated by 7.3.
NOTE 8—When preparing specimens from certain composite laminates
such as woven roving, or glass cloth, care must be exercised in cutting the
specimens parallel to the reinforcement. The reinforcement will be
significantly weakened by cutting on a bias, resulting in lower laminate
properties, unless testing of specimens in a direction other than parallel
with the reinforcement constitutes a variable being studied.
NOTE 9—Specimens prepared by injection molding may have different
tensile properties than specimens prepared by machining or die-cutting
because of the orientation induced. This effect may be more pronounced
in specimens with narrow sections.
6.2 Rigid Tubes—The test specimen for rigid tubes shall be
as shown in Fig. 2. The length, L, shall be as shown in the table
in Fig. 2. A groove shall be machined around the outside of the
specimen at the center of its length so that the wall section after
machining shall be 60 % of the original nominal wall thickness.
This groove shall consist of a straight section 57.2 mm
(2.25 in.) in length with a radius of 76 mm (3 in.) at each end
joining it to the outside diameter. Steel or brass plugs havin
NOTE 7—Test results have shown that for some materials such as glasscloth, SMC, and BMC laminates, other specimen types should beconsidered to ensure breakage within the gage length of the specimen, asmandated by 7.3.NOTE 8—When preparing specimens from certain composite laminatessuch as woven roving, or glass cloth, care must be exercised in cutting thespecimens parallel to the reinforcement. The reinforcement will besignificantly weakened by cutting on a bias, resulting in lower laminateproperties, unless testing of specimens in a direction other than parallelwith the reinforcement constitutes a variable being studied.NOTE 9—Specimens prepared by injection molding may have differenttensile properties than specimens prepared by machining or die-cuttingbecause of the orientation induced. This effect may be more pronouncedin specimens with narrow sections.6.2 Rigid Tubes—The test specimen for rigid tubes shall beas shown in Fig. 2. The length, L, shall be as shown in the tablein Fig. 2. A groove shall be machined around the outside of thespecimen at the center of its length so that the wall section aftermachining shall be 60 % of the original nominal wall thickness.This groove shall consist of a straight section 57.2 mm(2.25 in.) in length with a radius of 76 mm (3 in.) at each endjoining it to the outside diameter. Steel or brass plugs havin
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