1-3 Random Fiber Composites

Smart Material manufactures 1-3 composites using piezo ceramic fibers as active rods. PZT fiber composites are a cost-effective alternative compared to the the Dice & Fill method.
1-3 fiber piezo composites are prepared by epoxy infiltration of fiber bundles and dicing of the cube-shaped blocks perpendicular to the direction of the fibers. This patented method is also called Arrange & Fill.

Using piezo ceramic fibers with 105µm, 250µm and 800µm diameters yields fill factors of approx. 35%, 65% and 80% in a random distributed cross-section.

The random fiber composite material shows superior properties for ultrasound transduction, which is due to reduced acoustic impedance and high coupling factor. Additionally, 1-3 fiber composites with random element distribution yield an increased spurious mode suppression due to the random spacing.

Typical Ultrasound Applications for 1-3 Random Fiber Composites

  • NDT, Non-Destructive Testing
  • SONAR, single element transducer
  • Air Ultrasound Transducer
  • Flow Control and Measurement

Due to the Arrange & Fill production method the raw 1-3 fiber composite material are typical blocks of up to 10cm length and the lateral dimensions of the targeted element.

The A&F method also allows to machine 1-3 composites into various shapes and forms, in addition to slicing elements with the desired resonance frequency of the raw fiber block.

Plano-Concave This includes precise concave or convex contours for superior broadband ultrasound receiver applications.

The Arrange & Fill production method is easily scale-able for volume quantities which also allows for short lead time, a major advantage over the commonly used Dice & Fill method.

Smart Material offers various standard Epoxy and Polyurethane systems as the interstitial material for its random fiber composites, often called filler. The different, available filler materials allow for operational temperatures between 95°C and 130°C.

1-3 Random Fiber Composite product specifications and selections

Resonance Frequencies40kHZ up to 8MHz
Frequency Fiber Diameter (Pixel) Fill Factor Dimensions mm² Availability
40kHz - 1MHz 105µm, 250µm
800µm
35%, 65%
80%
max. 100 x 100 4-6 weeks
1MHz - 5MHz 105µm, 250µm 35%, 65% max. 100 x 100 4-6 weeks
5MHz - 8MHz 105µm 25% - 65% max. 100 x 100 4-6 weeks
Frequency Tolerances:
± 10% typical
± 5% on request
Fill Factors25%, 65%, 80%
Fill Factor Frequency Availability
35% 40kHz to 8MHz 4-6 weeks
65% 40kHz to 5MHz 4-6 weeks
80% 40MHz to 1MHz 4-6 weeks
PZT MaterialsPZT Navy Type II, VI
PZT Material Di-electric Constant Frequency Availability
PZT Navy Type II, 5A 1850 40kHz to 10MHz 4-6 weeks
PZT Navy Type VI, 5H 3850 40kHz to 10 MHz 4-6 weeks
Acoustic Impedance12 MRayl to 27 MRayl
Typical Fill Factors Acoustic Impedance MRayl
35% 12 MRayl
65% 22 MRayl
80% 27 MRayl
Available ElectrodesCuSn (Copper with Tin flash layer)
Au (Gold)
Electrode Material Frequency
CuSn 40kHz to 1MHz
CuSn, Au 1MHz to 8MHz
DimensionsMax. 100mm by 100mm,
various round diameters
Maximum Dimensions Frequency Availability
100mm by 100mm 40kHz to 5MHz 4-6 weeks
65mm by 65mm 5MHz to 8MHz 4-6 weeks
Mechanical Tolerances:
< 6mm ± 0.1mm
< 30mm ± 0.2mm
> 30mm ± 0.3mm
Available Diameters mm Available Diameters inch Available Diameters mm Available Diameters inch
3.18 mm 0.125 '' 12.70 mm 0.500 ''
5.12 mm 0.202 '' 14.20 mm 0.559 ''
5.18 mm 0.204 '' 15.90 mm 0.626 ''
5.68 mm 0.224 '' 17.50 mm 0.689 ''
6.00 mm 0.236 '' 18.00 mm 0.709 ''
6.50 mm 0.256 '' 19.05 mm 0.750 ''
8.20 mm 0.323 '' 20.00 mm 0.787 ''
9.00 mm 0.354 '' 24.00 mm 0.945 ''
9.50 mm 0.374 '' 25.40 mm 1 ''
10.00 mm 0.394 '' 30.00 mm 1.181 ''
10.20 mm 0.402 '' 35.00 mm 1.378 ''
12.00 mm 0.472 '' 37.7 1.48 ''
Coupling Coefficient kt0.61 to 0.68
Operational TemperaturesTypical 95°C, 130°C on request
Interstitial MaterialsVarious Epoxy systems