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 cleaner should be formulated for its method of application. It should also be understood that while these procedures are broadly applicable, particular substrates may require certain specific cleaning procedures.
If the plant conditions water for acidity or alkalinity care must be taken to be sure the solids content is not too high Note 1. Aluminum requires care to avoid overetching in alkaline cleaners; both aluminum and zinc are sensitive to pitting attack, zinc and brass to tarnishing.
These stages are discussed in three parts: Negatively charged ions and colloids are attracted to the parts. Methods of removal of heat-treat or mill scale are not included in these methods, because they are covered in practices referring to specific metals. This standard has been approved for use by agencies of the Department of Defense.
The use of clean gloves should be mandatory after buffing or polishing to avoid? Stop-off materials, when used, should be applied carefully in astmm to avoid contaminating signi? Bacteriostats can be included in the formulations of cleaners to prevent the unpleasant odors that result from bacterial action. Anodic electrocleaning solutions have much more tolerance for chromic acid contamination.
However, their concentration must be low enough to prevent excessive foaming caused by the evolution of hydrogen and oxygen at the 6 electrodes. Investigate introduction b322 any new soils that might cause the cleaner to become exhausted prematurely. It should also be astm b that while these procedures are broadly applicable, particular substrates may require certain specific cleaning procedures.
Prolonged storage or drying of emulsion drawing compounds after metal working should be avoided so that slimy water-in-oil emulsions do not form. It can be eliminated by lowering the cleaner temperature, decreasing transfer time, installing fog nozzles to keep parts wet until they reach rinse tanks, or by using cleaners b32 to prevent staining of sensitive nonferrous metals.
A cleaner may be very effective for one group of soils, yet poor for other soils. Positively charged ions and colloids are attracted to the cathode. Although agitation is better than in some cleaning, control is frequently not as good. Some electroplaters use the term precleaning for alkaline cleaning before electrocleaning, especially when solvent cleaning is carried out at a different part of the plant. Because data on methods and results of evaluation with electroplated astm b on tung Methods of removal of astm b or mill scale are not included in t Alkaline chelated derusting and cleaning solutions, alone or with sodium cyanide, used as a awtm or electrocleaner, are often preferred before electroplating on ferrous alloys.
For more specific safety precautionary statements see Sections 11 and The higher temperatures remove soils more quickly and effectively, but caution must be used with cleaners containing organics of low? This time is shortened if agitation is vigorous, temperatures high, and concentration high.
ASTM B – 99() Standard Guide for Cleaning Metals Prior to Electroplating
One procedure involves scrubbing with pumice and then comparing the surface produced by this method with that produced under production conditions. Thus, specially compounded soak cleaners can remove rust, heat scale, and iron or zinc phosphate deposits as well as oily or other soils.
B22 addition of emulsi? This is followed by immersion in cold solvent to cool the parts. Otherwise, antifoaming ingredients are a part of the formulations. Because most experience and knowledge in cleaning have been obtained by suppliers of proprietary processes and aetm, these sources should be consulted before setting up a cleaning process.
The degree of cleanliness required for metals to be electroplated is greater than for most other finishes.
v322 ICS Number Code Usually, even with light soils, it is advisable to retain multistage cleaning, thereby increasing the life and efficiency of the cleaning solutions. Because of the low cost of diluted emulsion cleaners, it is economical to discard these baths at frequent intervals.
BGM Fastener Grade 8 Product Specifications
Temperature also is a critical operating parameter. The organic surface-active agents chosen should not xstm decomposed into tarry residues by heat, high alkalinity, or oxidation at anodes. Therefore, other materials must be incorporated with the sodium hydroxide. Alloys of lead, nickel, or silver and nickel, and silver electroplated surfaces should not be anodically cleaned.