DICE & FILL COMPOSITES
1-3 Dice and Fill composites
Smart Material manufactures 1-3 composites using the standard Dice and Fill method, which is the industry standard above 500 kHz.
A 1-3 Dice and Fill composite starts as a piezo ceramic plate, which is diced into an orthogonal array to 80 to 90 per cent of its thickness. The pitch between rods has to be very small, typically around 100 µm at a 5 MHz resonance frequency, to avoid lateral modes and grating lobes.
The kerfs are filled with epoxy or another polymer. Once the interstitial material has cured, the uncut side of the ceramic is ground down to the rod structure and the thickness is adjusted to the target resonance frequency. The result is the regular pixel or rod distribution that phased array ultrasound transducers require.
- Frequencies from 500 kHz to 12 MHz
- PZT Navy types I, II, III and VI
- Fill factors from 25 to 75 per cent
- Single crystal PMN-PT
- Maximum size 8 cm by 8 cm, larger and curved parts on request
- A choice of epoxy and polyurethane interstitial materials
- Operating temperatures up to 135 ℃
- Gold or copper tin electrodes
Product specifications and options
| Property | Range |
|---|---|
| Resonance frequencies | 500 kHz to 15 MHz |
| Fill factors | 25 to 75 per cent |
| PZT materials | PZT Navy types I, II, III and VI, and single crystal PMN-PT |
| Acoustic impedance | 8.5 to 26 MRayl |
| Electrodes | CuSn (copper with a tin flash layer) or Au (gold) |
| Dimensions | Up to 75 x 75 mm, and a range of round diameters |
| Coupling coefficient kt | 0.61 to 0.68 for standard PZT materials, above 0.75 for single crystal |
| Operating temperatures | Typically 95 ℃, or 135 ℃ on request |
| Interstitial materials | A range of epoxy systems |
By frequency
| Frequency | Pixel size | Fill factor | Dimensions (mm²) |
|---|---|---|---|
| 500 kHz to 1 MHz | 400 to 800 µm | 25 to 75% | max. 75 x 75 |
| 1 to 2 MHz | 150 to 350 µm | 25 to 75% | max. 75 x 75 |
| 2 to 6 MHz | 55 to 200 µm | 25 to 75% | max. 75 x 75 |
| 6 to 8 MHz | 75 to 100 µm | 35 to 65% | max. 35 x 35 |
| 8 to 10 MHz | 40 to 75 µm | 50 to 60% | max. 35 x 35 |
| 10 to 15 MHz | 15 to 35 µm | 50 to 60% | max. 35 x 35 |
PZT materials
| Material | Dielectric constant | Frequency range |
|---|---|---|
| PZT Navy type I, SP4 | 1,200 to 1,300 | 500 kHz to 8 MHz |
| PZT Navy type II, 5A | 1,850 to 2,000 | 500 kHz to 10 MHz |
| PZT Navy type III, PZT8 | about 1,050 | 500 kHz to 8 MHz |
| PZT Navy type VI, 5H | 3,200 to 6,200 | 500 kHz to 10 MHz |
| Single crystal PMN-PT | 4,000 to 7,500 | 2 to 10 MHz |
Acoustic impedance by fill factor
| Fill factor | Acoustic impedance |
|---|---|
| 25% | 8.5 MRayl |
| 35% | 12 MRayl |
| 50% | 17 MRayl |
| 65% | 22 MRayl |
| 75% | 25 to 26 MRayl |
Electrodes
| Electrode | Frequency range | Thickness |
|---|---|---|
| CuSn, copper with a tin flash layer | 500 kHz to 8 MHz | about 1.5 µm |
| Au, gold | 4 to 10 MHz | about 0.8 µm |
Maximum dimensions
| Maximum size | Frequency range |
|---|---|
| 75 x 75 mm | 500 kHz to 6 MHz |
| 35 x 35 mm | 6 to 8 MHz |
| 30 x 30 mm | 8 to 10 MHz |
Available diameters
| Diameter | Inches | Diameter | Inches |
|---|---|---|---|
| 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 mm | 1.48″ |
Typical ultrasound applications
- Non destructive testing
- Medical ultrasound
- Flow control and measurement
- Phased array transducers for non destructive testing
How it compares
Dice and Fill generally costs more than a comparable 1-3 fiber composite made by the Arrange and Fill method, because it involves extra production steps and scales less easily to volume.
Smart Material also has the machining capacity to make curved 1-3 Dice and Fill composites, as well as complex array structures and interconnects.
Specify a composite with us
Send us your frequency, fill factor and size and Smart Material will quote for a composite built to that specification.
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