Product Data Sheet – TIEDE MF-655 WB (MAGNAGLO WB-655)

Water-based Fluorescent Magnetic Ink

TIEDE® MF-655 WB is a liquid concentrates used to prepare water-based fluorescent inks for wet method magnetic particle testing. Inks produced using MF-655 WB give clear bright yellow/green indications when viewed in a darkened area under UV(A) of peak wavelength 365 nm, and offer enhanced corrosion protection.

When used in conjunction with suitable magnetising equipment and a UV(A) source, MF-655 WB inks will locate fine surface and slightly subsurface defects.

Chemical product icon - fluorescent magnetic


  • Clear, bright indications under UV light
  • High sensitivity
  • Easy post-testing clean up
  • Excellent fluorescent contrast for quick identification
  • Excellent particle mobility
  • Good dispersion stability
  • Great concentration consistency
  • Superior surface wetting
  • Non-foaming
  • Even surface coverage for better detection
  • Enhanced corrosion protection – meets Corrosion Level 0 according to DIN 51360
  • Free from silicone, chromates and nitrates
  • Non-hazardous


Defect location: surface and slightly subsurface

Ideal for:

  • Detecting very fine to fine discontinuities
  • Machined parts
  • Smooth surface finish
  • Critical applications
  • High volume testing
  • After secondary processing
  • Mixing with hard-water

Defect examples:

  • Inclusions
  • Seams
  • Shrink cracks
  • Tears
  • Laps
  • Flakes
  • Welding defects
  • Grinding cracks
  • Quenching cracks
  • Fatigue cracks


A mixture of fluorescent magnetic particles, corrosion inhibitor, wetting agents and foam control additives.

Specification Compliance

  • AFNOR NF A 029-125
  • AMS3044
  • ASME B & PV Code, Sec V
  • ASTM E709
  • ASTM E1444/E1444M
  • DIN 54132
  • EN ISO 9934-2
  • GOST R ISO 9934-2-2011
  • MIL-STD-271F
  • MIL-STD-2132D
  • NAVSEA 250-1500-1
  • SAE AS4792

Product Properties

Form and color Brown liquid
SAE sensitivity 7 – 8
Density 1.1 g/ml
Particle size range 3 – 5 µm
Settlement volume (1 hour) 0.21 ml (1:40 ratio); 0.13 ml (1:60 ratio)
pH (2% solution) 9.1
Storage temperature 10°C to 30°C
Usage temperature 5°C to 55°C

Like all Magnaflux materials, MF-655 WB is closely controlled to ensure batch-to-batch consistency, optimum process control and inspection reliability.

User Recommendations

NDT Method Magnetic Particle Testing, Fluorescent, Wet Method
Storage temperature 10°C to 30°C
Usage temperature 5°C to 55°C
Suspension vehicle Water
Water bath additive WA-1 water conditioner; WA-2 antifoam
Cleaner SKC-S
UV lamps
EV6000; ST700
Centrifuge Tube

Instructions for Use

Clean the component before testing to provide a suitable test surface.

Use an appropriate measuring device to make up the ink bath based on the following guide volumes:

Quantity of MF-655 WB Quantity of water,
ratio 1:40
Quantity of water,
ratio 1: 60
0.5 litres (500 ml) 19.5 litres 29.5 litres
0.75 litres (750 ml) 29.25 litres 44.25 litres
1 litre (1000 ml) 39 litres 59 litres

Once the bottle is empty, rinse it with water to capture any remaining product and add this to the bath. Mix thoroughly and check that the bath has the correct settlement volume before use.

Settlement volumes (after 1 hour):
0.21 ml (1:40 ratio)
0.13 ml (1:60 ratio)

Apply the ink by spraying, flooding or immersion, depending on your chosen method (see below).

Wet continuous method
Apply the ink to all surfaces of the component and apply a magnetising current. Remember to stop the flow of ink before the current is switched off, otherwise the force of the ink flood can wash away indications.

Wet residual method
This method is generally less sensitive than the continuous method and is more susceptible to rapid particle depletion and bath contamination.

  • Pre-magnetise the part to be tested.
  • Immerse the part in a bath of the ink.
  • Remove it and allow it to drain.
  • Inspect the part.

Be sure to agitate the ink before and regularly during use to ensure uniformity of mix. During use, the magnetic content of any ink will become depleted so you will need to check your bath strength at least once each day. The most widely-used way of checking an ink’s settlement volume is by using a graduated ASTM pear-shaped centrifuge tube.

When the settlement volume approaches the lower limit, check the bath. If it appears contaminated, or if it has been in use for a long time, replace the contents. If it is still clean and uncontaminated, you can add more MF-655 wB to the bath. As before, make sure that the ink is agitated immediately prior to use to ensure complete mixing of the contents.

After inspection, remember to completely de-magnetise your components before cleaning, to ensure easy removal of any residual powder particles. Cleaned components can be treated with a temporary film protective coating if you need longer-lasting corrosion protection.

Packaging and Part Numbers

Part number 061C061

Packaging icon: 1 litre plastic bottle

Part number 061C062

Packaging icon: 5 litre plastic bottle

Health & Safety

Review all relevant health and safety information before using this product. For complete health and safety information, refer to the relevant Safety Data Sheet.

Download this Product Data Sheet as a PDF