Page 15 - Automotive Aerospace

Examples of Applicable Standards

ASTM D 3039 /D 3039M-07
ASTM D 3518 /D 3518M-94
ASTM D 5766 /D 5766M-11
Static Tensile Testing of CFRP
Tensile testing was performed on JIS K7073-1988 Type IV samples (strip sample
with no tabs, fiber direction perpendicular to direction of tensile load), with an
Width sensor
extensometer attached for strain measurement in tensile direction and a width perpendicular Extensometer in
to tensile direction tensile direction
sensor to measure strain perpendicular to the tensile direction.
Poisson's ratio is approximately 0.3 for mild steel and 0.46 to 0.49 for elastic
rubber. However, the value of 0.06 is an order of magnitude smaller for CFRP, Sample
showing that its deformations are extremely low.
Before After
test fracture

Stress (MPa) Stress (MPa)

Tensile modulus calculated as 5.76 × 10 5 MP
across 100 to 300 MPa stress range
Poisson's ratio calculated as 6.0 × 10 -2
across 100 to 300 MPa stress range

Displacement gauge 1 (strain) (%) Width sensor (mm)
Stress – Strain Diagram Stress – Width-Direction Displacement Diagram

ASTM E1012
Axial Adjustment for Testing
Axial adjustment of the tester is extremely important to reduce the risk of breaking samples at the chuck
during tensile testing of CFRP or GFRP. Axial adjustment is often a prerequisite for the stable acquisition of
data for aircraft-grade CFRP.
This axial adjustment system provides a test environment conforming to ASTM E1012, enhancing the
reliability of the data.

Axial Adjustment System
The axial adjustment system uses an axial-center sensor, strain amplifier unit, and special axial adjustment
software to adjust the inclination between grip centers and to adjust the axis in the horizontal direction.
Eliminating bending stresses and lateral shear stresses on the sample ensures highly reliable data.

Axial Adjustment Software
When loads are applied to the special sample, this dedicated software reads the signals from the strain
gauge attached to the sample. The axis can be adjusted by manual movements of the adjustment jig based
on this information.

Testing and Evaluation Equipment
for the Aerospace Industry
Solutions for Aerospace Testing 15