ASTM Standards: B Practice for Operating Salt Spray (Fog) Apparatus2. B Guide for Engineering Chromium Electroplating3. B Practice for. Endorsed by AmericanDesignation: B – 01 (Reapproved )e1. ASTM B/BM() Standard Guide for Engineering Chromium Electroplating Scope
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ASTM B177/B177M – 11(2017)
Need more than one copy? B — 01 Endorsed by American Electroplaters’ Society Endorsed by National Association of Metal Finishers Standard Guide for Engineering Chromium Electroplating1 This standard is issued under the xed designation B ; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision.
This standard is not included in any packages. When using test methods in which a zinc immersion lm is applied to the aluminum surface for protection against oxide formation, the article to be plated must enter the chromiumplating solution under live current. This guide is not intended as a standardized procedure, but as a guide for obtaining smooth, adherent coatings of xstm desired thickness while retaining the required physical and mechanical properties of the base metals.
Specified chromium electrodeposits on ferrous surfaces are defined in Specification B The bake should be performed as soon as possible after the parts are removed from the plating bath, rinsed, and dried in order to reduce the risk of hydrogen embrittlement. Nonmagnetic Coatings on Magnetic Basis Metals. If a nondestructive method is required, magnetic induction methods in accordance with Test Method B are suitable for chromium over magnetic substrates. Subscription pricing is determined by: The bond strengths of the chromium varies with metallic substrate.
Standard Guide for Engineering Chromium Electroplating
Face shield, chemical goggles, astk gloves, and other safety equipment should be used when handling sulfuric acid and when making this addition. The most recent baths do not use uoride co-catalysts and do not etch unprotected atsm current density areas.
Chromium electrodeposits do not exhibit leveling, and consequently the surface roughness of the electrodeposit will always be greater than that of the substrate.
Steel or ferrous parts to be plated are allowed to reach the bath temperature and electroplating is then commenced. Combining values from the two systems may result in non-conformance with the standard.
ASTM B/BM – 11() – Standard Guide for Engineering Chromium Electroplating
A superscript epsilon e indicates an editorial change since the last revision or reapproval. Consult with appropriate safety manuals or safety personnel, or both, before handling sulfuric acid or chromic acid! Platinum, platinumclad zstm, or even steel rods or wire may be used for internal electroplating of small holes, but the latter will contaminate the bath with iron.
This is normally used on highly nished steel requiring only a aastm chromium deposit as its use may result in less adhesion than other procedures and in hydrogen embrittlement of the steel.
The main difficulty with these materials when chromium plating is b1177 of the nickel alloy surface prior to plating which results in deactivation of the material and skip plating. Last previous edition B — For parts loaded in compression or not subject to cyclical applications of stress during operation, or both, this may not asgm a consideration. This process is much simpler than that in 6. The deposits are dull gray in color and can be buffed, if desired.
In operating these baths, it is essential that no sulfate be introduced into the bath. Please first verify your email before subscribing to alerts. This condition will greatly reduce the fatigue life of the part and should be avoided. Unique activation procedures for steel exist with chromium plating that merit a separate discussion for successful plating as follows.
Due to the high carbon content in iron castings, anodic etching leaves a carbon smut on the surface of the metal which results in poor adhesion of the chromium.
In general, anodic etching in the chromium plating solution is not recommended. Specified chromium electrodeposits on ferrous surfaces are defined in Specification B Lead wire used for small anodes should contain 0.
It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use n177 application. To reduce the increase in roughness resulting from etching, the etching times should be kept as short as is consistent with good adhesion, particularly in the case awtm highly nished surfaces.
Chemical lead is also satisfactory where hardness and rigidity are awtm important. When direct measurement of the thickness of the coating is desired and the part can be sacriced, it should be done in accordance with Test Method B