非常急，在线等
5.4.6 After conditioning the specimen is to be placed in the grips of the power-driven testing machine so that the bench marks are between and not covered by the grips. The movable grip is to be adjusted to make the specimen taut but not under tension. The grips are to be separated at the rate specified in 5.4.4 until rupture. During separation ,the distance between bench marks is to be measured and recorded at the point of rupture to the nearest 0.1 inch (2.5mm).
5.4.7 Calculations are to be made for each of the specimens and averaged using the following formulas. Specimen measurements for the calculation of the area are to be made before aging and exposure.
a) Tensile strength, psi equals F/A in which:
F is the maximum observed force in pounds.
A is the cross-sectional area of the unstressed specimen in square inches. See (b-(e).
b) Cross-sectional area of die- cut or straight specimen equals W x T in which:
W is the width of the constricted portion of the dir-cut or straight specimen in inches.
T is the minimum thickness of the specimen in inches.
c) Cross-sectional area of “O” ring specimens and specimens with a circular cross-section equals 037854 D2 in which:
D is the cross-sectional diameter in inches as measured in accordance with Table 5.1.
d) Cross-sectional area of tubular specimen equals 0.7854(D2-d2) in which;
D is the outside diameter in inches and d is the internal diameter in inches.
e) Cross-sectional area for irregular shaped specimens equals W/163.87G in which:
W is the grams mass (to the nearest 0.005 g ) of a specimen length or lengths totaling 10 inches (254mm).
G is the specific gravity of the compound. The specific gravity may be determined by means of the following: G=W1/(W1+W3-W2) in which:
W1 is the gram mass on the balance pan of the specimen (to the nearest 0.005 g).
W2 is the gram mass of the fully immersed specimen and its partially immersed suspending wire (to the nearest 0.005g).
W3 is the gram mass of the partially immersed suspending wire.
Reference may be made to Test Method for Specific Gravity and Density of Plastics by Displacement, ASTM D792-91.
f) Elongation percent equals 「(L-Lo)/Lo」x100 in which:
L is the measured distance between the bench marks at rupture.
Lo is the original distance between the bench marks.
5.4.6 After conditioning the specimen is to be placed in the grips of the power-driven testing machine so that the bench marks are between and not covered by the grips. The movable grip is to be adjusted to make the specimen taut but not under tension. The grips are to be separated at the rate specified in 5.4.4 until rupture. During separation ,the distance between bench marks is to be measured and recorded at the point of rupture to the nearest 0.1 inch (2.5mm).
5.4.7 Calculations are to be made for each of the specimens and averaged using the following formulas. Specimen measurements for the calculation of the area are to be made before aging and exposure.
a) Tensile strength, psi equals F/A in which:
F is the maximum observed force in pounds.
A is the cross-sectional area of the unstressed specimen in square inches. See (b-(e).
b) Cross-sectional area of die- cut or straight specimen equals W x T in which:
W is the width of the constricted portion of the dir-cut or straight specimen in inches.
T is the minimum thickness of the specimen in inches.
c) Cross-sectional area of “O” ring specimens and specimens with a circular cross-section equals 037854 D2 in which:
D is the cross-sectional diameter in inches as measured in accordance with Table 5.1.
d) Cross-sectional area of tubular specimen equals 0.7854(D2-d2) in which;
D is the outside diameter in inches and d is the internal diameter in inches.
e) Cross-sectional area for irregular shaped specimens equals W/163.87G in which:
W is the grams mass (to the nearest 0.005 g ) of a specimen length or lengths totaling 10 inches (254mm).
G is the specific gravity of the compound. The specific gravity may be determined by means of the following: G=W1/(W1+W3-W2) in which:
W1 is the gram mass on the balance pan of the specimen (to the nearest 0.005 g).
W2 is the gram mass of the fully immersed specimen and its partially immersed suspending wire (to the nearest 0.005g).
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