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Reducing Weight

Improving CAE Reliability for Composite Materials
– 3 Point Bending Impact Testing and

High-Speed Compression Testing of Composite Materials –

Evaluating the Strain Rate and Temperature Dependence of CFRP (3 Point Bending Impact Test) Evaluations for Improving the Accuracy of Plastic Product Impact Analysis
– Evaluating the Strain Rate Dependency of Resins –
Carbon fiber reinforced plastics (CFRP) offer high specific strength and specific stiffness. Therefore, they are used to improve the fuel efficiency of aircraft,
automobiles, and other transportation equipment by reducing their weight. In the case of automobiles, for example, their temperature characteristics are
Increasing the testing speed for polyamide with 15 % glass fiber and polypropylene increased the yield strength and decreased the elongation at failure.
especially important, due to their use in cold and desert climates. It is also important to evaluate their impact characteristics, due to their potential exposure
This shows that even for the same material, material characteristics can change significantly depending on the loading rate. Therefore, it is important to
to large instantaneous forces during accidents. In this example, thermoplastic CFRP test specimens were evaluated by a 3 point bending impact test.
obtain physical property data at expected loading rates before analysis.
High-Speed Puncture Impact Test Fixture
Testing Machine (3 Point Bending Impact Test)
HITS-PX High-Speed Tensile Testing Machine
HITS-TX
Indenter Test Conditions
Test · 0.0013 to 7.5 m/sec
specimen · -30 to 100 °C
CMT
(room temperature)
Test Specimen
Discontinuous Carbon Fiber Mat Reinforced
Thermoplastics Composite (CMT)
Thermocouple Dimensions : 50 × 100 × 2 mm 0.0001 to 20 m/sec
6
CF : T700 The results show that flexural strength is higher at lower temperatures (6 to 1.2 × 10 mm/min)
Plastic : Polypropylene and higher strain rate, which means that the flexural strength of
Vf : 20 % thermoplastic CFRP materials depends on the temperature and strain rate.
8.3 × 10 to 0.017 m/sec
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This research was performed as part of the "Research and Development of Innovative New Structural Materials" project commissioned by METI and NEDO (since 2014).
We are particularly grateful to Toray Industries for supplying the materials. (0.0005 to 1000 mm/min)
· Testing is possible at a wide range of speeds, from 0.0001 m/s to 20 m/s (72 km/h).
· Hydraulic control results in less speed damping during testing than for the weight-drop method.
· Testing is possible within the -40 °C to 150 °C range (optional).
· Because test specimens are immobilized to prevent movement from impacts, the fixture includes a spring mechanism that
secures the test specimens in position. Precision Universal Testing Machine
AGX-V Series

Analysis of GFRP failure behavior during high-speed compression testing
Stress vs. Chuck Displacement Curve Stress vs. Chuck Displacement Curve
Compression
Data analysis results Results of experiment Black line: Tensile speed 0.1 m/s Black line: Tensile speed 0.1 m/s
Top end of
sample Green line: Tensile speed 1.0 m/s Green line: Tensile speed 1.0 m/s
Actual test data
Blue line: Tensile speed 5.0 m/s Blue line: Tensile speed 5.0 m/s
Load (N) Stress (MPa) Stress (MPa)

HITS-X Series High-Speed HyperVision HPV Series Impact after sample failure is
Puncture Testing Machine High-Speed Video Camera absorbed by cushioning material.
Testing speed: 10 m/sec, Sample: GFRP
Observations of actual Simulation results
behavior provide
feedback for simulation
mode.
20 µsec
Time (sec) Data provided by: Nitto Boseki Co., Ltd.
The comparison confirmed extremely good correlation between results obtained
by actual testing and by simulation. Chuck displacement (mm) Chuck displacement (mm)
Evaluating the Speed Dependence of Polypropylene Evaluating the Strain Rate Dependence of Polyamide (with 15 % GF)
· Enables high-speed compression testing at speeds up to 10 m/sec. Shimadzu's proprietary impact interference function
protects the instrument from impacts after impacting samples. It minimizes vibration from impacts and enables highly
accurate high-speed compression testing. · Hydraulic actuation provides stable speeds even during high-speed testing.
· A maximum 10 Mfps high-speed video camera with high time resolution enables detailed observation of failure behavior · The high sampling frequency ensures ample time resolution for measuring high-speed behavior.
and further increases data reliability. · Tests can be performed in temperature environments ranging from -40 °C to +150 °C.

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