1、Designation: A1074 11 (Reapproved 2015)Standard Specification forHot Tin and Hot Tin/Lead Dip on Ferrous and Non-FerrousMetals1This standard is issued under the fixed designation A1074; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers tin and tin/lead coatings ap-plied by the hot dip process on ferrous and non-
3、ferrous metals.hot tin and tin/lead coatings are used to provide a lowcontact-resistance surface, to protect against corrosion, tofacilitate soldering, to provide anti-galling properties, and to bea stop-off coating in the nitriding of high-strength steels.1.2 This specification is intended to be ap
4、plicable to itemsthat are reflowed, centrifuged or otherwise handled to removeexcess tin or tin/lead bath metal. Coating thickness graderequirements reflect this.1.3 Some corrosion can be expected from tin or tin/leadcoatings exposed outdoors. In normal indoor exposure, tin ortin/lead is protective
5、on iron, steel, nickel, copper, and theiralloys. Corrosion can be expected at discontinuities in thecoating (such as pores) due to galvanic couples formedbetween the tin or the tin/lead and the underlying metal throughthe discontinuities, especially in humid atmospheres.1.4 This specification applie
6、s to hot tin dip coatings of notless than 99.8 % tin and to hot tin/lead dip coatings of 60 65 % tin and the balance lead.1.5 This specification does not apply to electrodepositedcoatings of tin or tin/lead.1.6 The values stated in SI units are to be regarded as thestandard. The values given in pare
7、ntheses are for informationonly.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitati
8、ons prior to use.2. Referenced Documents2.1 ASTM Standards:2A902 Terminology Relating to Metallic Coated Steel Prod-uctsB32 Specification for Solder MetalB183 Practice for Preparation of Low-Carbon Steel forElectroplatingB242 Guide for Preparation of High-Carbon Steel for Elec-troplatingB281 Practic
9、e for Preparation of Copper and Copper-BaseAlloys for Electroplating and Conversion CoatingsB320 Practice for Preparation of Iron Castings for Electro-platingB322 Guide for Cleaning Metals Prior to ElectroplatingB339 Specification for Pig TinB374 Terminology Relating to ElectroplatingB487 Test Metho
10、d for Measurement of Metal and OxideCoating Thickness by Microscopical Examination ofCross SectionB499 Test Method for Measurement of Coating Thicknessesby the Magnetic Method: Nonmagnetic Coatings onMagnetic Basis MetalsB504 Test Method for Measurement of Thickness of Metal-lic Coatings by the Coul
11、ometric MethodB558 Practice for Preparation of Nickel Alloys for Electro-platingB567 Test Method for Measurement of Coating Thicknessby the Beta Backscatter MethodB568 Test Method for Measurement of Coating Thicknessby X-Ray SpectrometryB571 Practice for Qualitative Adhesion Testing of MetallicCoati
12、ngsB602 Test Method for Attribute Sampling of Metallic andInorganic CoatingsB659 Guide for Measuring Thickness of Metallic and Inor-ganic CoatingsB678 Test Method for Solderability of Metallic-CoatedProducts1This specification is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron an
13、d Steel Products and is the direct responsibility ofSubcommittee A05.13 on Structural Shapes and Hardware Specifications.Current edition approved Oct. 1, 2015. Published October 2015. Originallyapproved in 2011. Last previous edition approved in 2011 as A1074-11.DOI:10.1520/A1074 -11R15.2For referen
14、ced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Co
15、nshohocken, PA 19428-2959. United States1B697 Guide for Selection of Sampling Plans for Inspectionof Electrodeposited Metallic and Inorganic CoatingsB762 Test Method of Variables Sampling of Metallic andInorganic CoatingsB849 Specification for Pre-Treatments of Iron or Steel forReducing Risk of Hydr
16、ogen EmbrittlementB851 Specification for Automated Controlled Shot Peeningof Metallic Articles Prior to Nickel, Autocatalytic Nickel,or Chromium Plating, or as Final FinishD3951 Practice for Commercial Packaging3. Terminology3.1 Definitions:3.1.1 The following terms and definitions are specific to t
17、hisspecification. Many of the terms used in this specification aredefined in Terminologies A902 and B374.3.1.2 sectional, nscreen section for placing articles intothe hot tin dip so that the articles do not stick together3.1.3 significant surface, nthe portion of the surface of acoated article at wh
18、ich the coating is required to meet all of therequirements of the coating specification for that article.Significant surfaces are usually those that are essential to theserviceability or function of the article, or that can be a sourceof corrosion products or tarnish films that interfere with thefun
19、ction or desirable appearance of the article. Significantsurfaces shall be indicated on the drawing of the parts or by theprovision of suitably marked samples.3.1.4 undercoat, nalso call an underplate in theelectronics/plating industry (see 3.1.5).3.1.5 underplating, napplication of a metallic coati
20、nglayer between the base metal or substrate and the topmostmetallic coating or coatings. The thickness of such an under-coating is usually greater them 50 microinches. This is incontrast to strikes or flashes, whose thicknesses are generallymuch smaller.4. Ordering Information4.1 In order to make th
21、e application of this specificationcomplete, the purchaser must supply the following informationto the seller in the purchase order and drawings:4.1.1 Title, ASTM designation number, and year of issue ofthis specification;4.1.2 Coating thickness requirement;4.1.3 Composition and metallurgical condit
22、ion of the sub-strate to be coated;4.1.4 Additional underplate, if required;4.1.5 Location of significant surfaces;4.1.6 Hydrogen embrittlement relief, if required; and4.1.7 Any other items needing agreement between pur-chaser and coater.5. Materials and Manufacture5.1 The specification, grade, or d
23、esignation and type as wellas the degree of surface contamination of the substrate materialshall be supplied by the purchaser to the hot tin dip coater priorto coating.5.2 The design and fabrication of the product to be hot tindip coated are the responsibility of the designer and thefabricator. Cons
24、ultation between the designer, the fabricator,and the coater at appropriate stages in the design and fabrica-tion process will reduce future problems.5.3 The tin used in the hot tin dip process shall conform toSpecification B339 and shall not be less than 99.8 % pure tin.5.4 The tin/lead used in the
25、 hot dip tin/lead process shallconform to Specification B32 and shall contain 60 % 6 5 % tinand the balance lead.5.5 The metal substrate shall be subject to such surfacepreparation, cleaning, underplating, and hot tin dip proceduresas are necessary to yield deposits with the desired quality.Careful
26、preparation of metal surfaces is necessary in order toassure good adhesion and quality. For suitable methods, seePractices B183, B242, B281, B320, B322, and B558.5.6 Hot tin dip or hot tin/lead dip shall be applied after allbasis metal heat treatments, mechanical operations, propercleaning, and unde
27、rcoats (if applicable) have been completed.6. Coating Requirements6.1 The appearance of the coated product shall be uniformthroughout, insofar as the base metal will permit. The finishshall be adherent and visually free from uncoated areas,blisters, flux deposits, dross inclusions, pits, peeled area
28、s,cracks, nodules and other types of projections that wouldinterfere with the intended use of the articles, or other defectsnot consistent with good hot tin dip or hot tin/lead practice.They shall not be stained or discolored and free of dewettedareas and beads. All surfaces shall be free of grease
29、or oil usedin the process.6.2 The hot tin dip or hot tin/lead dip coating shall besmooth and reasonably uniform in thickness. Smoothness ofsurface is a relative term. Minor roughness that does notinterfere with the intended use of the part, or roughness that isrelated to the as-received surface cond
30、ition of the part, shall notbe grounds for rejection.NOTE 1Since this specification is applicable to items that arecentrifuged and reflowed to remove excess bath metal (see 1.2), irregularcoating distribution is not normally encountered.6.3 The hot tin dip or hot tin/lead dip coating shall adhereten
31、aciously to the surface of the base metal or undercoat(undercoat as required, requested or needed to facilitateadhesion, suppress migration of tin into base metal or other).6.4 If the hot tin dipped or hot tin/lead dipped materialcovered by this specification is bent or otherwise fabricated tothe de
32、gree that causes the coating to stretch or compressbeyond the limit of elasticity, any cracking or flaking of thecoating resulting from the post coating bending or fabricatingshall not be cause for rejection.6.5 All hot tin dip or hot tin/lead dip articles shall be cleanand undamaged. When necessary
33、, preliminary samples show-ing the finish shall be supplied to and approved by thepurchaser.6.6 Thickness of CoatingWhere hot tin dip and hot tin/lead dip are molten processes, the thickness of coating can notbe built up in excess. After centrifuge and/or reflowing of theA1074 11 (2015)2articles, th
34、e mean value for finished thickness will range from100-300 microinches. This range yields a smooth, solderablefinish.6.7 Underplating6.7.1 For substrates of steel, brass, and other copper alloys,the hot tin dip or hot tin/lead dip finish can be applied directlyonto the base metal.6.7.2 To prevent zi
35、nc migration and impairment of solder-ability during service or storage, substrates of brass or othercopper alloys must have a copper undercoating of at least 100microinches, or a nickel undercoating of at least 50 micro-inches prior to hot tin or hot tin/lead dipping. A thicker coatingof nickel may
36、 be required in some situations for additionalretardation and improved adhesion.6.7.3 Other substrates such as aluminum, stainless steel, andkovar must have an electroless nickel coating undercoating inorder for hot dipped coatings to adhere properly.6.8 Hydrogen Embrittlement ReliefHigh-tensile str
37、engthsteels and severely cold worked steels are susceptible toembrittlement by hydrogen in both cleaning and hot tin and hottin/lead dipping. See Supplementary Requirements for details.7. Sampling7.1 The sampling plan used for inspection of the quantity ofthe coated articles shall be agreed upon bet
38、ween the purchaserand the supplier.7.2 The procedure for sampling is accomplished by select-ing a relatively small number of the finished articles at random.These articles (the inspection lots) are inspected and classifiedas complying or not complying with the requirements of thespecification. The s
39、ize of the sample and the criteria ofcompliance are determined by the application of statistics. Theprocedure is known as sampling inspection. The sampling plancan be selected by following the guidelines in Guide B697.These standards, Test Method B602, Test Method B762,MIL-STD-105, and MIL-STD- 1916
40、, contain sampling plansthat are designed for the sampling inspection of coatings.7.3 An inspection lot shall be defined as a collection ofcoated articles that meet the following requirements: they areof the same kind; have been produced to the same specifica-tions; have been coated by a single supp
41、lier at one time, or atapproximately the same time, under essentially identical con-ditions; and are submitted for acceptance or rejection as agroup.7.4 Special Test SpecimensIt may be preferable to usespecial test specimens to represent product in process controlor in acceptance inspection when, fo
42、r example, destructivetests are used and it is desirable not to destroy product or if thetest specimen is better adapted to the test. The use of specialtest specimens, their number, the material for which they aremade, their size and shape, and the conditions of their coatingshall be agreed upon by
43、the purchaser and the seller.8. Tests8.1 Deposit PurityAtomic absorption or energy dispersionspectrophotometry, or any other method with a demonstrateduncertainty of less than 10 % of the component measured, maybe used to determine The quantity of impurities in the tin ortin/lead baths. Initial scan
44、ning should be conducted for allelements in order to detect any unknown or unexpectedimpurities. Determine deposit purity by subtracting the totalquantity of impurities from 100 %.8.1.1 Deposit purity is best determined on samples of theactual product. If special test specimens are used, care must b
45、etaken to arrange the specimens so as to hot tin dip or hottin/lead dip them under the same conditions as typical produc-tion pieces.8.2 ThicknessThe coating thickness shall be measured atlocations on significant surfaces by one of the following testmethods: Test Methods B487, B499 (magnetic substra
46、tesonly), B504, B567,orB568. Practice B659 may be consultedto determine the most appropriate test method.8.3 AdhesionAdhesion of the coating is not normallytested on each lot of samples but, if there is an issue withadhesion then samples shall be tested by one of the recom-mended methods of Practice
47、 B571 or other method agreed toby the purchaser and the supplier.8.4 SolderabilityFor coatings that must be solderable, themethod by which solderability is tested shall be agreed to bythe purchaser and the supplier.Asimple dip test is given in TestMethod B678, while two other methods are described i
48、nAppendix X1. The purchaser shall specify whether the testarticles are to receive an artificial aging treatment, such as thatgiven in Test Method B678, so as to demonstrate whether thearticles may be expected to retain solderability during longstorage periods9. Inspection9.1 The inspector representi
49、ng the purchaser shall haveaccess at all times while work on the contract of the purchaseris being performed, to those areas of the manufacturers workwhich concern the application of the hot tin dip or hot tin/leadcoating to the material ordered. The manufacturer shall affordthe inspector all reasonable facilities to satisfy him that the hottin coating is being furnished in accordance with this specifi-cation. All inspection and tests shall be made at the place ofmanufacture prior to shipments, unless otherwise specified, andshall be so conducted as not to interfere unnec
