Aptflex F28
Part of a family of high frequency acoustic absorbers and provides the most cost effective method of absorbing unwanted ultrasonic reflection and acoustic isolation.
Overview
For anechoic test tank linings
AptFlex F28 is part of a family of high frequency acoustic absorbers and provides the most cost effective method of absorbing unwanted ultrasonic reflection and acoustic isolation. Other high frequency absorbers within the range provide higher levels of echo reduction.
Ultrasonic tank wall linings
Acoustic output measurements or ultrasonic testing, in general, can be strongly affected by reflections or echoes from test tank walls. This is particularly true for long tone burst or continuous-wave ultrasonic applications. To overcome this, test tanks should be coated with linings which must be of low ultrasonic reflection yet highly absorbent to ultrasound. NPL’s material has been designed specifically to meet this requirement.
Its simple design, being a single layer, ensures that the material is the cost-effective solution for coating large areas such as the walls of an ultrasonic test tank.
High insertion loss, approximated by 30 dB/cm/MHz. Insertion loss at frequencies greater than 2 MHz is in excess of 60 dB. This exceeds the dynamic range of the measurement and hence no more detailed data is available.
Key features
- Blue polyurethane rubber material, single-ply nominally homogeneous layer
- Thickness of tile: 10 mm, tile dimensions: 300 mm x 300 mm or 1200 mm x 600 mm
- Material can be cut using a sharp craft knife into various geometries to meet exact end-user requirements
- Density of 1.01 g/m3, is close to that of water
- Specific gravity 1.01
- Longitudinal wave speed (1 MHz to 10 MHz) approx. 1500 m/s
- Acoustic impedance 1.5 MRayls
- Resistant to: isopropyl alcohol (IPA); trichlorethylene
- Affected by: dichloromethane -swells. Avoid prolonged exposure to ozone and UV
- Stability: very stable due to cross-linked nature of polymer
- High echo-reduction, >22 dB at 1 MHz, degrading to ~15 dB at 10 MHz
- Echo-reduction >18 dB over frequency range 1 MHz to 3 MHz
