1、Designation: B607 91 (Reapproved 2014)Standard Specification forAutocatalytic Nickel Boron Coatings for Engineering Use1This standard is issued under the fixed designation B607; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 Nickel boron coatings are
3、 produced by autocatalytic(electroless) deposition from aqueous solutions. These solu-tions contain either an alkylamineborane or sodium borohy-dride as a reducing agent, a source of nickel ions, a buffer,complexant, and control chemicals.1.2 This specification describes the requirements for coat-in
4、gs of autocatalytic nickel boron deposited from aqueoussolutions onto substrates for engineering use. The specificationclassifies these coatings into two types:1.2.1 Type 1 coatings have a boron content of 0.1 to lessthan 3.5 mass percent with the balance nickel.1.2.2 Type 2 coatings have a boron co
5、ntent of 3.5 to 6 masspercent and a minimum of 90 mass percent nickel.1.3 The coatings are hard and uniform in thickness, even onirregular shaped parts, and used in a wide range of applications.1.4 Process solutions formulated with an alkylamineboraneusually produce coatings that contain 0.1 to 3.5
6、% boron. Thincoatings of this type provide bondability and solderability onelectronic components such as lead frames, electrical contacts,and headers. To maintain solderability, these coatings aregenerally not heat treated.1.5 Process solutions formulated with sodium borohydrideare strongly alkaline
7、 and are frequently used to plate steel andtitanium parts to impart surface hardness and wear resistanceproperties. Deposits produced from these processes can contain3 to 5 % boron and thallium or other metals which are used tostabilize the plating solution and modify the coating properties.1.6 The
8、physical and mechanical properties of these depos-its such as density, hardness, stress, and melting point will varywith the boron content. The variation of boron content alsoaffects the quantity and structure of nickel boride precipitatedduring heat treatment. In the as-plated condition the deposit
9、consists of a predominantly amorphous mixture of nickel andboron with a hardness of about 700 HKN. When the deposit isheated above 300C the nickel crystallizes, forming nickelclusters of Ni (111) and boron precipitates as nickel boride,Ni3B (211) and (311), increasing the hardness to greater than100
10、0 HK100for Type 2 coatings.1.7 The nickel boron coatings are microporous and offerlimited corrosion protection. Their columnar structure,however, is beneficial in reducing wear because it provides ameans of trapping lubricants within the surface of the coatedpart.1.8 This document describes only aut
11、ocatalytic nickel boroncoatings that have been produced without use of externalelectric sources.1.9 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.10 The following hazards caveat pertains only to the TestMethods section of th
12、is specification: This standard does notpurport to address the safety problems associated with its use.It is the responsibility of the user of this standard to establishappropriate safety and health practices and determine theapplicability of regulatory limitations prior to use.NOTE 1The following A
13、MS standards are not requirements. They arereferenced for information only: AMS 2399 and AMS 2433.2. Referenced Documents2.1 ASTM Standards:2B374 Terminology Relating to ElectroplatingB487 Test Method for Measurement of Metal and OxideCoating Thickness by Microscopical Examination ofCross SectionB56
14、7 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 MetallicCoatings1This specification is under the jurisdiction of ASTM Committee B08 onMetallic a
15、nd Inorganic Coatings and is the direct responsibility of SubcommitteeB08.03 on Engineering Coatings.Current edition approved Nov. 1, 2014. Published November 2014. Originallyapproved in 1991. Last previous edition approved in 2009 as B607 91 (2009).DOI: 10.1520/B0607-91R14.2For referenced ASTM stan
16、dards, 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 Conshohocken, P
17、A 19428-2959. United States1B578 Test Method for Microhardness of Electroplated Coat-ingsB602 Test Method for Attribute Sampling of Metallic andInorganic CoatingsB656 Guide for Autocatalytic (Electroless) Nickel-Phosphorus Deposition on Metals for Engineering Use(Discontinued 2000) (Withdrawn 2000)3
18、B667 Practice for Construction and Use of a Probe forMeasuring Electrical Contact ResistanceB678 Test Method for Solderability of Metallic-CoatedProductsB697 Guide for Selection of Sampling Plans for Inspectionof Electrodeposited Metallic and Inorganic CoatingsB762 Test Method of Variables Sampling
19、of Metallic andInorganic CoatingsD2670 Test Method for Measuring Wear Properties of FluidLubricants (Falex Pin and Vee Block Method)D2714 Test Method for Calibration and Operation of theFalex Block-on-Ring Friction and Wear Testing MachineE39 Methods for Chemical Analysis of Nickel (Withdrawn1995)3F
20、519 Test Method for Mechanical Hydrogen EmbrittlementEvaluation of Plating/Coating Processes and Service En-vironments2.2 Aerospace Materials Specifications:AMS 2399 Electroless Nickel-Boron Plating4AMS 2433 Electroless Nickel-Thallium-Boron Plating42.3 U.S. Government Standards:MIL-STD-105 Sampling
21、 Procedures and Tables for Inspec-tion by Attributes5MIL-STD-13165 Shot Peening of Metal Parts53. Terminology3.1 Definitions: Many terms used in this specificationaredefined in Terminology B374.3.2 Definitions of Terms Specific to This Standard:3.2.1 cold shuta void on the surface which has beenclos
22、ed by machining and then partially opened through clean-ing.3.2.2 hot halide stress-corrosion crackinga type of me-chanical failure produced by halogenated solvents that havebeen absorbed onto titanium and then in the presence of heatcause microcracking, and the loss of mechanical strength.3.2.3 lap
23、 cracksa surface imperfection caused by coldworking of steels producing a void which can be duplicated inthe deposit.3.2.4 significant surfacethose substrate surfaces which thecoating must protect and that are essential to the appearance.4. Classification4.1 The classification by type of these coati
24、ngs establishesthe amount of boron in the alloy.4.1.1 Type 1Coatings shall contain 0.1 to less than 3.5mass percent boron with the balance nickel.4.1.2 Type 2Coatings shall contain 3.5 to 6 mass percentboron and a minimum of 90 mass percent nickel.4.2 The classification by class of these coatings es
25、tablishesthe post treatment to be performed on the part(s). The posttreatment steps are designed to reduce the potential forhydrogen embrittlement, increase the adhesion of the coatingto the substrate, improve the fatigue properties of the part(s),and increase the wear resistance and hardness of the
26、 coating:4.2.1 Class 1Parts are supplied as plated with no post heattreatment.4.2.2 Class 2Parts are heat treated after plating to increasehardness. The coating is heat treated at 365 to 385C for 90min (see 7.2.4).4.2.3 Class 3Parts are heat treated after plating at 180 to200C for 2 to 23 h to impro
27、ve coating adhesion on steel andfor hydrogen embrittlement relief of steels (see 7.2.4).4.2.4 Class 4Parts are heat treated after plating at 120 to130C for a minimum of1htoimprove adhesion onheat-treatable (age-hardened) aluminum alloys and carburizedsteels (see 7.2.4).4.2.5 Class 5Parts are heat tr
28、eated after plating at 365 to375C for a minimum of4htoimprove adhesion on titaniumand titanium alloys (see 7.2.4).4.3 The classification by grade establishes the minimumthickness of the coating:4.3.1 Grade AParts are plated to a minimum coatingthickness of 0.5 m.4.3.2 Grade BParts are plated to a mi
29、nimum coatingthickness of 12 m.4.3.3 Grade CParts are plated to a minimum coatingthickness of 25 m.4.3.4 Grade DParts are plated to a minimum coatingthickness of 75 m.5. Ordering Information5.1 The purchaser should be aware of several processingconsiderations or options available to the processor an
30、d whenordering should supply the information described in 5.1.1through 5.1.15 in the purchase order and drawings.5.1.1 Title, ASTM designation, and year of issue of thisspecification.5.1.2 Composition and metallurgical condition of the basismetal, assemblies of dissimilar materials must be identifie
31、d.5.1.3 Classification of the coating: type, class, and grade forthis specification (see Section 4).5.1.4 Minimum thickness required on the significantsurface, and any maximum dimensions or tolerancerequirements, if any (see 7.2.2).5.1.5 Method of adhesion testing from Test Method B571 tobe used in
32、acceptance requirements (see 8.3).5.1.6 Requirements for certification and test reports (seeSection 11).5.1.7 Requirements for heat treatment of the part(s) forstress relief prior to plating (see 7.2.4).5.1.8 Optional sampling plan for lot inspection of the part(s)(see 9.1 and 13.1).3The last approv
33、ed version of this historical standard is referenced onwww.astm.org.4Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.5Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 1911
34、1-5094, Attn: NPODS.B607 91 (2014)25.1.9 Increased sampling frequency, if any, for qualificationtests (see 7.3).5.1.10 Supplemental requirements for shot peening of thepart(s) (see 12.1).5.1.11 Supplemental requirements for wear testing (see 12.2and 12.3).5.1.12 Supplemental requirements for heat tr
35、eatment invacuum or inert or reducing atmosphere (see 7.2.1 see 9.2) is examined for compliance with the requirements placed on theparts, a relatively small number of partsthe sampleis selected atrandom and inspected. The inspection lot is then classified as complyingor not complying with the requir
36、ements based on the results of theinspection sample. The size of the sample and the criteria of complianceare determined by the application of statistics. The procedure is known assampling inspection. Test Method B602, Guide B697, and Method B762contain sampling plans that are designed for the sampl
37、ing inspection ofcoatings.Test Method B602 contains four sampling plans, three for use with teststhat are nondestructive and one for use with tests that are destructive. Thepurchaser and producer may agree on the plan(s) to be used. If they do not,Test Method B602 identifies the plan to be used.Guid
38、e B697 provides a large number of plans and also gives guidanceon the selection of a plan. When Guide B697 is specified, the purchaserand producer need to agree on the plan to be used.Method B762 can be used only for coating requirements that have anumerical limit, such as coating thickness. The tes
39、t must yield a numericalvalue and certain statistical requirements must be met. Method B762contains several plans and also gives instructions for calculating plans tomeet special needs. The purchaser and producer may agree on the plan(s)to be used. If they do not, Method B762 identifies the plan to
40、be used.TABLE 2 Heat Hardening of Nickel Boron DepositsTemperature, C Time, min37510 90TABLE 3 Post Heat Treatment for Class 4 and 5 CoatingsClass Temperature, C Time, minimum, hClass 4 125 5 1Class 5 370 5 4B607 91 (2014)49.2 An inspection lot shall be defined as a collection ofcoated parts that ar
41、e of the same kind, that have been producedto the same specification, that have been coated by a singleproducer at one time or approximately the same time underessentially identical conditions, and that are submitted foracceptance or rejection as a group.9.3 If separate test specimens are used to re
42、present thepart(s) in the test, the number shall be that required in 8.1.10. Rejection and Rehearing10.1 Part(s) that fail to conform to the requirements of thisspecificationmay be rejected. Rejection shall be reported to theproducer promptly in writing. In the case of dissatisfactionwith the result
43、s of a test, the producer may make a claim for arehearing. Coatings that show imperfections may be rejected.11. Certification11.1 When specified in the purchase order or contract, thepurchaser shall be furnished certification that the samplesrepresenting each lot have been processed, tested, and in-
44、spected as directed in this specification and the requirementshave been met. When specified in the purchase order orcontract, a report of the test results shall be furnished.12. Supplementary Requirements12.1 Shot PeeningWhen specified by the purchaser in theordering information, the part(s) shall b
45、e shot peened prior toplating in accordance with MIL-STD-13165.12.2 Abrasive WearWhen specified by the purchaser inthe ordering information, the coating shall be tested forabrasion wear resistance using the procedure described inAppendix X2 of this specification. The coating shall meet amaximum wear
46、 rate which is specified by the purchaser andagreed to by the producer.12.3 Adhesive WearWhen specified by the purchaser inthe ordering information, the coating shall be tested foradhesive wear resistance using Test Method D2714 or D2670.The wear rate shall be specified by the purchaser and agreed t
47、oby the producer.12.4 Inert AtmosphereWhen specified by the purchaser inthe ordering information, the coating shall be heat treated in avacuum or an inert or reducing atmosphere to prevent surfaceoxidation of the coating.12.5 Contact ResistanceWhen specified by the purchaserin the ordering informati
48、on, the coating shall be tested forcontact resistance using Practice B667.12.6 SolderabilityWhen specified by the purchaser in theordering information, the unaged coating shall pass TestMethod B678.13. Special Government Regulations13.1 SamplingThe producer when plating part(s) for theU.S. governmen
49、t and military use shall use a sampling planfrom MIL-STD-105.13.2 Shot PeeningHigh strength steel part(s) processedfor U.S. government and military use shall be shot peened inaccordance with MIL-STD-13165.APPENDIXES(Nonmandatory Information)X1. DENSITY OF NICKEL BORON COATINGSX1.1 Many thickness test methods measure the mass perunit area and display the thickness in linear units. These testmethods require a density factor to calculate the thickness. Fig.X1.1 can be used to determine the density of nickel coatingswith varying boron content
