Parts are rack or barrel plated to ASTM B standard thicknesses from ” to “, depending on the base metal and application. Pure % tin is. Designation: B – 97 (Reapproved )e1 Standard Speci?cation for Electrodeposited Coatings of Tin1 This standard is issued under the. ASTM B Standard Specification for Electrodeposited Coatings of Tin.
|Published (Last):||20 June 2007|
|PDF File Size:||18.90 Mb|
|ePub File Size:||10.58 Mb|
|Price:||Free* [*Free Regsitration Required]|
MIL-T-10727 vs. ASTM B545
This specification covers the requirements asttm electrodeposited tin coatings b455 to metallic articles to provide a low contact resistance surface, to protect against corrosion, to facilitate soldering, to provide anti-galling properties, and to be a stop-off coating in the nitriding of high-strength steels.
Test Method B contains several plans and also provides instructions for calculating plans to meet special needs. Parts coated with tin can be assembled safely in contact with iron and steel, tin-coated aluminum, yellow chromated zinc, cadmium, and solder coatings.
An underplating of nickel or copper must be used as a diffusion barrier on brass. The size of the sample and the criteria of compliance are determined by the application of asym. See Supplementary Requirements S1 and S2 for details. Porosity increases as the coating thickness decreases, so that minimum thicknesses must be specified for each application. B5545 Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard.
Product that shows coating imperfections in subsequent manufacturing operations may be rejected.
Parts coated with tin can be assembled safely in contact with iron and steel, tin-coated aluminum, yellow chromated zinc, cadmium, and solder coatings. All surfaces shall be substantially free of grease or oil used in the? B5545 coatings are used to provide a low contact-resistance surface, to protect against corrosion see 1. Similar to Class A, but for shorter-term contact applications and short shelf-life requirements, subject to purchaser approval.
Examination of 43 magni? A bright coating completely covering the signi?
ASTM B – 13 Standard Specification for Electrodeposited Coatings of Tin
Current edition approved April 1, The mechanical forces of the molten solder and tin? Corrosion can be expected at discontinuities in the coating such as pores due to galvanic couples formed between the tin and the underlying b554 through the discontinuities, especially in humid atmospheres. Guide B provides a large number of plans and also provides guidance in the selection of a plan. The test must yield a numerical value, and certain statistical requirements must be met.
Rejection shall be reported to the seller promptly and in writing. For some applications, this requirement may be relaxed to allow for a small number of such defects per unit areaespecially if they are outside of or on the periphery of signi? NOTE 4—Thickness of electrodeposited coatings varies from point to point on the surfaces of b5545 product see Practice B In this specialized application, the occurrence of whisker growth is sufficiently frequent to be an obstacle to the use of tin.
The thickness of such an undercoating qstm usually greater than 0. Thicker coatings are used for water containers, threaded steel couplings of oil drilling strings, g545 seacoast atmospheres.
Poor adhesion will be shown by the appearance of a loose blister that grows as rubbing is continued. If the sulfur dioxide concentration in the atmosphere is too high, the corrosion product formed is too? Examples are electrical hardware such as cases for relays and coils, transformer cans, screened cages, chassis, frames, and? The size should be sufficient to accommodate aetm test specimens with their lowest part at least 75 mm 3 in. Remove the articles, rinse them in clean water, wipe and brush as necessary to remove smut antimony residues astmm, and dry.
This specification does not cover hot-dipped tin or other non-electrodeposited coatings, and mill products. Practice B may be consulted to determine the most appropriate test method.
Other coatings variations, such as surface appearance type 4.
Mild service conditions with less severe requirements than Class C below. Evidence of diffusion is the formation of a layer of copper-tin intermetallic at the interface and diffusion of zinc to the surface if the substrate ashm brass. Maintain pressure sufficient to burnish the? Coatings subject to mild etchants are included. Some tin coatings, especially of bright tin, may show? This abstract is a brief summary of the referenced standard.
Nonmagnetic Coatings on Magnetic Basis Metals. These should be taken into account when designing for special applications. For mill products, refer to Specifications A or AM.
Blackening at pores will be evidence of porosity.
ASTM B – Tin Plating by Keystone Finishing
The clamp is attached to a load cell and to a transducer, which transmits a signal to a converter that adjusts the signal to a useful mode analog or digital for the recording instrument, computer, or strip-chart recorder.
The amount of porosity in the coating that may ast, tolerable depends on the severity of the environment that the article is likely to encounter during service or storage. When Guide B is speci? Test Method B can be used only for coating requirements that have a numerical limit, such as coating thickness.
If the full thickness is required on these surfaces, the electroplater will have to use special techniques that probably will increase the cost of the process.