General Appearance
Britemor 446 is a clear, mobile, yellow-green liquid in daylight and appears brilliant yellow under UVA light of 365 nm peak wavelength (black light).
General Composition
Britemor 446 is a stable solution of solvents, non-ionic emulsifying agents and fluorescent dyes. It contains no added sulphur, halogen or inorganic compounds and is essentially ash free on ignition.
Temperature Stability
Britemor 446 remains stable without precipitation or separation and has good resistance to heat fade if subjected to prolonged or excessively high temperatures during processing. Britemor 446 is typically used for the inspection of critical components, particularly of complex geometry where a high level of sensitivity and excellent water washability and resistance to overwashing is required.
Sensitivity Level
Britemor 446 is approved to AMS 2644, Type 1, Method A, Level 3.
Typical Properties
Flash Point : > 100°C (212°F)
Viscosity at 40°C : approx. 9.5 mm2/s
Density at 20°C : approx. 0.93 g/cm3
Water Solubility : partly soluble
Surface Preparation
The successful application of penetrant is completely dependent on the ability of the penetrant to enter a defect which is open to the surface. All paint, organic coatings, oils, greases, carbon deposits, rust, scale, flux residues and any other contaminants must be removed completely before application of the penetrant. When aqueous cleaners are used, it is essential that the component is thoroughly dried before penetrant application as water entrapment could reduce the probability of defect detection.
Penetrant Application
Methods which can be used include immersion, flow-on, electrostatic, aerosol or conventional spray, brush-on and wipe-on. In the case of immersion, it is bad practice to drain on to a drip tray which allows the penetrant to run back into the tank. It is also important to ensure that the penetrant is allowed to drain from areas of entrapment caused by the geometry of the component. Ideal processing temperature for normal use of penetrant lies between 10 - 35°C (50 - 95°F).
Penetrant Contact (Dwell) Time
For immersion processes, contact time is the immersion time plus the drain time. Contact times are dependent on the component being tested and typical specifications may be 10 – 30 minutes. The surface temperature of the component should be less than 40°C (104°F) before application of penetrant.
Penetrant Removal
Removal by water washing should be carried out under UV background illumination to avoid over or under washing. Air or airless spray water pressures should be in accordance with the relevant specification. Immersion rinse can be used followed by a final spray wash. Water wash temperature is normally approx. 20°C (68°F) and this may also be stated in the specification.
Drying & Developing Drying temperatures of 60 - 80°C (140 - 176°F) are normal for oven drying. Ovens should be thermostatically controlled with clean, dry, re-circulating air and capable of drying the component in 10 minutes. Developers can be applied by spraying, dust storm cabinet or immersion in the case of water based developers. Inspection is normally carried out at least 10 minutes after developing.
Safety guidance
Before operating the process described it is important that this complete document, together with any relevant Safety Data sheets, be read and understood.
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Chemetall GmbH The above details have been compiled to the best of our Trakehner Str. 3 knowledge on the basis of thorough tests and with regard to the 60487 Frankfurt, Germany current state of our long practical experience. No liabilities or guarantees deriving from or in connection with this leaflet can be imputed to us. Reproduction, in whole or in part, only with www.aerospace.chemetall.com our express permission.
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