ASTM_B() – Designation: B – 91 (Reapproved ) and Inorganic Coatings2 B Guide for Autocatalytic (Electroless). ASTM-B, ASTM-B, Mil-CE. Services. Home · Electroless Nickel Plating · Copper Plating · Tin Plating · Silver Plating · Gold Plating · Line. astm b pdf astm b ()e1 Standard Practice for Porosity in Gold and Palladium Alloy Coatings on Metal Substrates by Vapors of Sodium Hypochlorite .
|Published (Last):||8 August 2018|
|PDF File Size:||15.22 Mb|
|ePub File Size:||13.3 Mb|
|Price:||Free* [*Free Regsitration Required]|
B — 91 Reapproved Standard Speci? A number in parentheses indicates the year of last asmt. A superscript epsilon e indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense. These solutions contain either an alkylamineborane or sodium borohydride as a reducing agent, a source of nickel ions, a buffer, complexant, and control chemicals.
Thin coatings of this type provide bondability and solderability on electronic components such as lead frames, electrical contacts, and headers.
To maintain solderability, these coatings are generally not heat treated. The variation of boron content also affects the quantity and structure of nickel boride precipitated during heat treatment. In the as-plated condition the deposit consists of a predominantly amorphous mixture of nickel and boron with a hardness of about HKN. Their columnar structure, however, is bene? This standard does not purport to address the safety problems associated with its use.
It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. They are referenced for information only: Current edition approved Sept. Originally approved in Last previous edition approved in as B — 91 The post treatment steps are designed to reduce the potential for hydrogen embrittlement, increase the adhesion of the coating to the substrate, improve the fatigue properties of the part sand increase the wear resistance and hardness of the coating: Government requirements, if any see Section Materials and Manufacture 6.
Imperfections in the surface of the basis material including scratches, porosity, pits, inclusions, roll and die marks, lap crack, burrs, cold shuts, and surface roughness that could adversely affect the coating should be brought to the attention of the purchaser prior to processing see 7.
The stress relief heat treatment can reduce the hardness of some alloys and should therefore be reviewed by all h656-91 before processing see 5. Shorter times and higher temperature can be used if the resulting loss of surface hardness is acceptable to the purchaser. Exposure of the parts to hydrogen sources will generally induce the condition. Care must be exercised whenever high strength steel is processed to ensure minimal exposure b66-91 timely relief treatment. Each lot of part s shall be sampled with the recommended procedure described in Section 9 of this speci?
A test specimen or part, processed in a manner that duplicates the characteristics of production parts, shall be produced and used in these tests.
The alloy produced shall be within the range speci? Calculate the thickness from the increase in mass, surface area, and density of the coating. NOTE 2—The density of the coating will decrease as the mass percent boron in the coating increases.
For Type 1 coatings the density is approximately 8.
Astm b656-91 pdf
Analyze the solution for nickel at From the results of the analysis calculate a fraction of the boron or alloying element divided by the total of boron, nickel, and alloying element. Report the percent boron and alloying element if present in the coating. The determination of mass percent boron content may be accomplished by an appropriate analytical method such as atomic absorption spectroscopy.
Report the percent boron and alloying elements if present in the coating. NOTE 4—Usually, when a collection of coated parts the inspection lot; see 9. The inspection lot is then classi? The size of the sample and the criteria of compliance are determined by the application of statistics.
Electroless Nickel |
The procedure is known as sampling inspection. Test Method BGuide Band Method B contain sampling plans that are designed for the sampling inspection of coatings. Test Method B contains four sampling plans, three for use with tests that are nondestructive satm one for use with tests that are destructive.
The purchaser and producer may agree on the plan s to be used. If they do not, Test Method B identi? Guide B provides a large number of plans and also gives guidance on the selection of a plan.
When Guide B b6566-91 speci?
qstm Method B can be used only for coating requirements that have a numerical limit, such as coating thickness. The test must yield a numerical value and certain statistical requirements must be met.
Method B contains several plans and also gives instructions for calculating plans to meet special needs. If they do not, Method B identi? Using a calibrated Vernier microscope, examine the thickness of the deposit and average over 10 readings using Test Method B NOTE 3—Microscopic metallographic sectioning is dependent on the sample preparation.
Ensure that the specimen is at the same temperature for each measurement and that the surface measured is smooth. This technique measures the mass per unit area of the coating applied over the substrate and is displayed as thickness.
The use of the beta backscatter method is restricted to basis metals that have an atomic number less than 18 or greater than The instrument shall be calibrated with specimens having the same basis material and coating composition as the part s. It can only be used for coatings of known boron content. Rejection and Rehearing Rejection shall be reported to the producer promptly in writing.
In the case of dissatisfaction with the results of a test, the producer may make a claim for a rehearing. Coatings that show imperfections may be rejected.
B — 91 The coating shall meet a maximum wear rate which is speci? The wear rate shall be speci? Special Government Regulations These test methods require a density factor to calculate the thickness.
The test is performed on a rotating plated panel that is abraded by two rotating rubber wheels. The panel is weighed before and after each cycles for weight loss determination. Duration of the test is cycles and it can be extended to 25 cycles. Care should be taken to control the humidity between tests as recommended by the equipment manufacturer. For each of the three specimens follow X2.
The wheels shall be loaded with g with the vacuum on high for the entire test. The results should be averaged without the?
To reface the wheels use CS discs. Report b6569-1 mean and standard deviation for the coating and the humidity during testing. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.
Users of this standard are expressly advised that determination of b656-9 validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every? Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters.
Your comments will receive careful consideration at a meeting of the astj technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. Individual reprints astk or multiple copies of this standard may be obtained by contacting ASTM at the above address or at phonefaxor service astm.