No one single property determines if a material will or will not be a good penetrant
Surface tension and wetting ability
It takes about 5 minutes for the bulb to warm up to its full output when first turned on
The lamp may go out if the line voltage drops below 90 volts
Line voltage variations above 120 volts will have little or no effect on the bulb
If for any reasons the arc is extinguished, the bulb will not immediately respond if the lamp is turned on right after it has been turned off.
The method can find all types of discontinuties
The method is simple in principle and relatively easy to understand.
The method is essentially simple in application.
There are few limitations on the size and shape of the article that can be treated by this method.
The penetrant test method is less flexible than eddy current test method
The penetrant test method is less reliable than the magnetic particle method for finding surface defects in ferromagnetic materials.
The penetrant test method will not detect fatigue cracks.
The penetrant test method is more reliable tha radioraphic testing when attempting to detect minute surface discontinuities.
Internal forging burst
Lack of penetration
Heat treat crack
The kind and size of discontinuities most likely to occur
The intended application for the part
The surface finish of the part
All of the above
The acid in the penetrant may cause severe corrosion
The alkaline content of wet developer and most emulsifiers could result in surface pitting, particularly in moist atomspheres.
The toxic residue from the test will severly inhibit the application of paint on aluminum alloys
A chemical reaction between the penetrant and aluminum could cause a fire because of internal combustion.
Core and mold material
All of the above
Cleaning with solvent type material
Hot water rinse
A dotted or smooth continuous line
A cluster of small indications
A rough deep indication
A large bulbous indication
A round or nearly round indication
A cluster of indications
A continuous line
A dotted line
Non Aqueous developer
High viscosity developer
Inadequate application of developer
Penetrant or part to cold during penetration time
Lint or dirt
Corrosion caused by the moisture attracted by such residues
Lattiice structure breakdown
Post cleaning process
Providing a clean surface
Providing a contrasting background
Providing a dry surface
Emulsifying the penetrant bleed-out
Reapplying a coat of emulsifier
Increasing the water pressure used during the washing operation
Completely reprocessing the part from surface preparation on and by using a longer emulsifier time.
Dipping the part in boiling water
100 foot candles