ASTM B – Designation: B – 99 (Reapproved ) Endorsed by American Electroplaters’ Socie. Find the most up-to-date version of ASTM B at Engineering International Auto and Engineering Works (IAEW), a year-old company based in Mumbai, follows the (The American Society for Testing and Materials) ASTM.
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The higher temperatures remove soils more quickly and effectively, but caution must be used with cleaners containing organics of low? ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.
ashm The cleaner should be buffered to have a high tolerance for acidic soils. Because of the rapid penetrating action of the solvent and solvent vapor, this method is effective in cleaning parts containing recesses, blind holes, perforations, crevices, and welded seams.
ASTM B322 – 99(2014)
Rate of solution, however, is frequently very slow in cold g322. Stop-off materials, when used, should be applied carefully in order to avoid contaminating signi? The atomizer test is the most sensitive one, but the water-break test is most commonly used. Part III -Final electrocleaning, to remove trace solids and especially adherent impurities.
The chlorinated solvents are very effective for many soils, but not as effective in removing soap-based or other solvent-insoluble soils. Foaming after soap accumulation also limits spray pressure. However, unless properly compounded, they can cause excessive foaming.
Zinc die castings have surfaces that require special care because of sensitivity to attack by cleaning solutions. You have successfully saved to your supplier list. Individual reprints single or multiple copies of this standard may be obtained by contacting ASTM at the above address or at phonefaxor service astm. To obtain true costs per thousand square feet of work processed astmm these factors must be included. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend.
In like manner, the recommendations for their application vary widely. Insulated joints on steam, drain, and water lines should be provided. However, their concentration must be low enough to prevent excessive foaming caused by the evolution of hydrogen and oxygen at the 6 electrodes. These must be in sufficient quantity to wet and emulsify residual oil and grease?
Often, depending largely on the amount and type of soil on the workpieces as received, one or more of these stages may be eliminated or modified. Foaming may be a problem, unless the cleaner is properly designed. Others prefer the safer but slower process of adding the cleaner directly to the tank of water at room temperature with provision for agitation to avoid caking. The use of automatic auxiliary stills in conjunction with the degreaser allows continuous cleaning operation and solvent recovery.
PR cleaning gives improved smut removal, accelerates cleaning operations, and provides a more active surface for subsequent electroplating It should also be understood that while these procedures are broadly applicable, particular substrates may require certain speci?
Additions of rust inhibitors or of aastm cleaners can be made to the water phase. Spray or soak alkaline cleaning also can be used as a precleaning stage followed by additional alkaline cleaning, if the soil and metal lend themselves to this treatment. Too high a current density when electrocleaning adtm will cause electroplating out of dissolved metals and some colloids as a smut. Too high a pH will result in lowering of the bacteria action, and oil will be built-up. If steam coils are used, check for leaks diluting the solution.
If any of these have been changed, they are to be considered a possible source of the trouble. For more specific safety precautionary statements see Sections 11 and Notes are optional and private.
ASTM B – 99() Standard Guide for Cleaning Metals Prior to Electroplating
If doubt exists as to polarity, check with a voltmeter, or trace back the conductors to the current source. The organic chelating agents are b232 and offer another advantage over the polyphosphates in that they solubilize light oxide?
With some cleaners, adequate rinsing is difficult to obtain after the cleaner has dried on the work. This is true of electrocleaners as well as soak or spray cleaners. Bacteriostats can be included in the formulations of cleaners to prevent the unpleasant odors that result from b32 action. The common electroplates applied are usually copper, nickel, and chromium for decorative and functional uses. This treatment activates the metal and is usually accomplished in acid baths which also serve to neutralize the residual alkaline?
Sometimes this can be traced back to vapor degreasing which removes the oil but not the solid particles. Hydrogen gas is evolved on the surface. This action, plus subsequent acid dip, before electroplating, removes disturbed metal surfaces and promotes better adhesion.
Agitation is very good in spray cleaning if the sprays hit the solid surfaces directly. Often, depending largely on the amount and type of soil on asym workpieces as received, one or more of these stages may be eliminated or modified. The most common cause is cleaner drying on the work during transfer.
Roughness also may be caused by incomplete rinsing of alkaline soak or electrocleaners due to excessive water hardness or an b3222 cleaner bath. If parts are to be held over between operations, a light oil or alkaline protective?
The common electroplates applied are usually copper, nickel, and chromium for decorative and functional uses. These stages are discussed in three parts: The cleaner should be formulated for its method of application.