Observation of Failure in CFRP Materials
Composite materials are attracting attention as strong, light replacements of metals as structural materials. Carbon-fiber reinforced plastics (CFRP) are attracting substantial interest as body materials in aircraft and automobiles, and considerable research is being conducted into their use as structural materials. To achieve such practical application targets, all kinds of evaluation and testing are conducted on composite materials. These include observations of the failure process of composite materials to enhance strength and improve the manufacturing process. A high-speed video camera is required to capture the failure process of CFRP materials, which is an extremely rapid brittle fracture phenomenon.
The failure process of CFRP was observed using a high-speed video camera.
- Fig. 1 shows an example of the failure process of a CFRP material.
- Test rate: 0.5 mm/minute; thickness: 1.13 mm
- A signal generated by the failure of aluminum foil stuck on the specimen was used as the trigger signal.
Failure started from a single point on the CFRP 0º UD material. Multiple vertical cracks (parallel to the fibers) then developed and the cracked specimen was seen to undulate as it failed.
Combination of a puncture impact testing machine and high-speed video camera allows simultaneous evaluation of impact properties and observation of the failure process. It supports the development of a wide range of materials from single functional resins to composite materials.
High-Speed Puncture Impact Testing Machine
Due to more stringent demands for safety and reliability, the dynamic strength (shock resistance) evaluation of materials and parts is becoming increasingly important. This testing machine obtains maximum test force, energy, and displacement data at speeds up to 72 km/h (20 m/s).
Two types are available: HITS-P10 High-Speed Puncture Impact Testing Machine and HITS-T10 High-Speed Tensile Testing Machine.
Takes 100 consecutive images at up to one million frames per second. Maintains a constant 312 x 260 pixel resolution up to the maximum frame rate. A single PC can control synchronous imaging with a maximum of four cameras to observe the phenomena from multiple viewpoints. Synchronizing imaging with the tensile testing machine offers comparative observations of stress data and high-speed images.