ASTM有色金属标准.B33

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Designation:B33–04
劳动后的心得体会Standard Specification for
Tinned Soft or Annealed Copper Wire for Electrical Purpos1
This standard is issued under thefixed designation B33;the number immediately following the designation indicates the year of original adoption or,in the ca of revision,the year of last revision.A number in parenthes indicates the year of last reapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.
This standard has been approved for u by agencies of the Department of Defen.
1.Scope
1.1This specification covers tinned,round,soft,or annealed copper wire for electrical purpos.
1.2The SI values for density and resistivity are to be regarded as standard.For all other properties the inch-pound values are to be regarded as the standard and the SI units may be approximate.
1.3This standard does not purport to address all of the safety concerns,if any,associated with its u.It is the responsibility of the ur of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to u.
新年愿望清单2.Referenced Documents
2.1ASTM Standards:2
B49Specification for Copper Redraw Rod for Electrical Purpos
B193Test Method for Resistivity of Electrical Conductor Materials
B258Specification for Standard Nominal Diameters and Cross-Sectional Areas of AWG Sizes of Solid Round Wires Ud as Electrical Conductors
2.2Other Document:3
NBS Handbook100Copper Wire Tables
3.Ordering Information
3.1Orders for material under this specification shall include the following information:
3.1.1Quantity of each size,
3.1.2Wire size-diameter in inches(e5.3and Table1),
3.1.3Type of copper,if special(e
4.2),
3.1.4Package size(e10.1),
3.1.5Special packaging marking,if required,and
3.1.6Place of inspection(e7.1).
4.Material
文言文句式类型4.1Tin for Coating—The tin ud for coating shall be commercially pure(Explanatory Note1).For purpos of this specification,the tin shall be considered commercially pure if the total of other elements,exclusive of copper,does not exceed1%.Notwithstanding the previous ntence,chemical analysis of the tin coating or of the tin ud for coating shall not be required under this specification.Adequacy of the tin coating is assured by the continuity of coating and adherence of coating requirements(e
5.4and5.5,respectively).
4.2Copper-Ba Metal—The ba metal shall be copper of such quality and purity that thefinished product shall have properties and characteristics prescribed in this specification. N OTE1—Specification B49defines copper suitable for u.
4.3Copper bars of special qualities,forms,or types,as may be agreed upon between the manufacturer and the purchar, and which will conform to the requirements prescribed in this specification,may also be ud.
5.General Requirements(See Section8)
5.1Tensile Strength and Elongation(Explanatory Note2 and Note3)—The tinned wire shall conform to the require-ments for elongation prescribed in Table1.No requirements for tensile strength are specified.For wire who nominal diameter is more than0.001in.(1mil)(0.025mm)greater than a size listed in Table1,but less than that of the next larger size, the requirements of the next larger size shall apply.
5.2Resistivity(Explanatory Note1and Note4)—The electrical resistivity of tinned wire at a temperature of20°C shall not exceed the values prescribed in Table2.
5.3Dimensions and Permissible Variations(Explanatory Note2)—The wire sizes shall be expresd as the diameter of the wire in decimal fractions of an inch to the nearest0.0001in.
(0.1mil)or in millimetres to the nearest0.0025mm.The
1This specification is under the jurisdiction of ASTM Committee B01on
Electrical Conductors and is the direct responsibility of Subcommittee B01.04on
Conductors of Copper and Copper Alloys.
Current edition approved Sept.1,2004.Published October2004.Originally
approved in1919.Last previous edition approved in2000as B33–00.
2For referenced ASTM standards,visit the ASTM website,,or
contact ASTM Customer Service at For Annual Book of ASTM
Standards volume information,refer to the standard’s Document Summary page on
the ASTM website.
3Available from National Technical Information Service(NTIS),U.S.Depart-
ment of Commerce,5285Port Royal Rd.,Springfield,V A22161.
1
Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.
tinned wire shall not vary from the specified diameter by more than the amounts prescribed in Table3.
5.4Continuity of Coating—The tin coating shall be con-tinuous.The continuity of coating on the wire shall be determined on reprentative samples taken before stranding or insulating.The continuity of tinning shall be determined by the hydrochloric acid-sodium polysulfide test in accordance with
6.4.
5.5Adherence of Coating—The tin coating shall befirmly adherent to the surface of the copper.The adherence of coating on the wire shall be determined on reprentative samples taken before stranding or insulating.The adherence of coating shall be determined by the wrapping and immersion test in accordance with
6.5.
5.6Joints—Necessary joints in the completed wire and in the wire and rods prior tofinal drawing shall be made in accordance with the best commercial practice.
5.7Finish—The coating shall consist of a smooth continu-ous layer,firmly adherent to the surface of the copper.The wire shall be free of all imperfections not consistent with the best commercial practice.
6.Test Methods
6.1Tensile Strength and Elongation(Explanatory Note 5)—No test for tensile strength shall be required.The elonga-tion of wire who nominal diameter is larger than0.0808in.买水
(2.052mm)in diameter shall be determined as the permanent increa in length,expresd in percent of the original length, due to the breaking of the wire in tension,measured between gage marks placed originally10in.(254mm)apart upon the test specimen.The elongation of wire who nominal diameter is0.0808in.and under may be determined as described above or by measurements made between the jaws of the testing machine.When the latter method is ud,the zero length shall be the distance between the jaws at the start of the tension test and be as near10in.as practicable and thefinal length shall be the distance between the jaws at the time of rupture.The fracture shall be between gage marks in the ca of specimens so marked or between the jaws of the testing machine and not clor than1in.(25.4mm)to either gage mark or either jaw.
6.2Resistivity(Expanatory Note4)—The electrical resistiv-ity of the material shall be determined in accordance with Test Method B193.The purchar may accept certification that the wire was drawn from rod stock meeting the international standard for annealed copper instead of resistivity tests on the finished wire.
6.3Dimensional Measurements—Dimensional measure-ments shall be made with a micrometre caliper equipped with a vernier graduated in0.0001in.(0.0025mm).Measurements shall be made on at least three places on each unit lected for this test.If accessible,one measurement shall be taken on each end and one near the middle.The average of the three measurements shall determine compliance with the require-ments.
TABLE1Tensile Requirements Diameter Area at20°C
< cmil in.2mm2Elongation in10in. (250mm), %min
0.460011.6840211600.000.166190107.219330 0.409610.4038167772.160.13176885.011430 0.36489.2659133079.040.10452067.432130 0.32498.2525105560.010.08290753.488030
0.28937.348283694.490.06573342.408625 0.2576  6.543066357.760.05211733.624025 0.2294  5.826852624.360.04133126.665225 0.2043  5.189241738.490.03278121.149225
0.1819  4.620333087.610.02598716.765725 0.1620  4.114826244.000.02061213.298025 0.1443  3.665220822.490.01635410.550925 0.1285  3.263916512.250.0129698.366925 0.1144  2.905813087.360.01027879  6.631525 0.1019  2.588310383.610.00815527  5.261520 0.0907  2.30388226.490.00646107  4.168420 0.0808  2.05236528.640.00512758  3.308120
0.0720  1.82885184.000.00407150  2.626820 0.0641  1.62814108.810.00322705  2.082020 0.0571  1.45033260.410.00256072  1.652120 0.0508  1.29032580.640.00202683  1.307620 0.0453  1.15062052.090.00161171  1.039820 0.0403  1.02361624.090.001275560.822920 0.03590.91191288.810.001012230.653020 0.03200.81281024.000.000804250.518920
0.02850.7239812.250.000637940.411620 0.02530.6426640.090.000502730.324320 0.02260.5740510.760.000401150.258820 0.02010.5105404.010.000317310.204715 0.01790.4547320.410.000251650.162415 0.01590.4039252.810.000198560.128115 0.01420.3607201.640.000158370.102215 0.01260.3200158.760.000124690.080415
0.01130.2870127.690.000100290.064715 0.01000.2540100.000.000078540.050710 0.00890.226179.210.000062210.040110 0.00800.203264.000.000050270.032410 0.00710.180350.410.000039590.025510 0.00630.160039.690.000031170.020110 0.00560.142231.360.000024630.015910 0.00500.127025.000.000019630.012710
0.00450.114320.250.000015900.010310 0.00400.101616.000.000012570.008110 0.00350.088912.250.000009620.006210 0.00310.07879.610.000007550.004910
TABLE2Electrical Resistivity Requirements
Nominal Diameter Resistivity at20° V·lb/mile2V·g/m2 0.460to0.290,incl11.7to7.4,incl896.150.15695 Under0.290to0.103,incl Under7.4to2.6,incl900.770.15776 Under0.103to0.0201,incl Under2.6to0.51,incl910.150.15940 Under0.0201to0.0111incl Under0.51to0.28,incl929.520.16279 Under0.0111to0.0030,incl Under0.28to0.076,incl939.510.16454
TABLE3Permissible Variations in Diamter Nominal Diameter of Wire
年终总结及明年计划Permissible Variations in Diameter
< in.mm plus minus plus minus Under0.0100Under0.250.00030.000100.00760.0025 0.0100and over0.25and over3%1%3%1
%
6.4Continuity of Coating:
6.4.1Specimens:
6.4.1.1Length of Specimens—Test specimens shall have a length of about6in.(152mm).They shall be tagged or marked to correspond with the coil,spool,or reel from which they were cut.
6.4.1.2Treatment of Specimens—The specimens shall be thoroughly cleaned by immersion in a suitable organic solvent such as benzene,ether,or trichloroethylene for at least3min; then removed and wiped dry with a clean,soft cloth(Caution-e Explanatory Note6).The specimens thus cleaned shall be kept wrapped in a clean,dry cloth until tested.That part of the specimen to be immerd in the test solution shall not be handled.Care shall be taken to avoid abrasion by the cut ends.
6.4.2Special Solutions Required:
6.4.2.1Hydrochloric Acid Solution(HCl)(sp gr1.088)—Commercial HCl(sp gr1.12)shall be diluted with distilled water to a specific gravity of1.088measured at15.6°C(60°F).
A portion of HCl solution having a volume of180mL shall be considered to be exhausted when the number of test specimens prescribed in Table4of a size as indicated in6.4.3have been immerd in it for two cycles.
6.4.2.2Sodium Polysulfide Solution(sp gr  1.142)(Ex-planatory Note7)—A concentrated solution shall be made by dissolving sodium sulfide cp crystals in distilled water until the solution is saturated at about21°C(70°F),and adding sufficient flowers of sulfur(in excess of250g/L of solution)to provide complete saturation,as shown by the prence in the solution of an excess of sulfur after the solution has been allowed to stand for at least24h.The test solution shall be made by diluting a portion of the concentrated solution with distilled water to a specific gravity of1.142at15.6°C(60°F).The sodium polysulfide test solution should have sufficient strength to blacken thoroughly a piece of clean untinned copper wire in 5s.A portion of the test solution ud for testing samples shall not be considered to be exhausted until it fails to blacken a piece of clean copper as described above.
6.4.3Procedure:
电脑如何截图快捷键6.4.3.1Immersion of Specimens—Immer a length of at least41⁄2in.(114mm)from each of the clean specimens,in accordance with the following cycles,in test solutions main-tained at a temperature between15.6and21°C(60and70°F): (1)Immer the specimen for1min in the HCl solution described in  6.4.2,wash,and wipe dry;(2)immer the specimen for30s in the sodium polysulfide solution described in6.4.2,wash,and wipe dry;(3)immer the specimen for1min in the HCl solution,wash,and dry;(4)immer the specimen for30s in the sodium polysulfide solution,wash,and wipe dry.
6.4.3.2Washing Specimens—After each immersion,imme-diately wash the specimens thoroughly in clean water and wipe dry with a clean,soft cloth.
6.4.3.3Examination of Specimens—After immersion and washing,examine the specimens to ascertain if copper expod through openings in the tin coating has been blackened by action of the sodium polysulfide.The specimens shall be considered to have failed if,by such blackening,expod copper is revealed.No attention shall be paid to blackening within0.5in.(12.7mm)of the cut end.A grayish brown appearance of the coating shall not constitute failure.
6.5Adherence of Coating:
6.5.1Specimens:
6.5.1.1Length of Specimens—Test specimens shall be ap-proximately12in.(305mm)in length and shall be tagged or marked to correspond with the coil,spool,or reel from which they are cut.
6.5.1.2Treatment of Specimens—The specimens shall be thoroughly cleaned,if required,by immersion in a suitable organic solvent such as benzene,ether,or trichloroethylene for at least3min,then removed and dried(Caution-e Explana-tory Note6).The specimens thus cleaned sh
all be kept wrapped in a clean dry cloth until tested.That part of the specimens to be immerd in the test solution shall not be handled.Care shall be taken to avoid abrasion of the surface to be subjected to test.Wire of sizes0.005in.(0.13mm)and smaller may be cleaned after wrapping around the mandrel.
6.5.2Procedure:
6.5.2.1Wrapping—Slowly wrap the test specimen in a suitable manner in an open helix around a polished mandrel having rounded ends and a diameter not to exceed four times the nominal diameter of the specimen.Take care not to stretch the specimen during the wrapping operation.The spacing of the concutive turns shall be approximately equal to the diameter of the wire.For sizes0.021in.(0.53mm)and smaller, not more than six helical turns shall be ud for the test,and for wire larger than0.021in.,not more than three turns shall be ud.
6.5.2.2Immersion Test—Remove the helically wrapped portion of the test specimen from the mandrel and immer completely in the sodium polysulfide solution(e6.4.2)for30 s at the temperature prescribed in6.4.3.On removal from the sodium polysulfide solution,immediately rin the specimen in clean water and remove the excess by shaking.
6.5.2.3Examination of Specimens—Examine visually the outer peripheral surface of the helically wrapped portion of the specimen.For wires0.021in.(0.53mm)and smaller,a magnification not greater than three times may be ud.Any cracking or parting of the coating in this area shown by blackening of the copper shall be cau for rejection.A grayish brown appearance of the coating after immersion shall not constitute failure.
6.6Finish—Surface-finish inspection shall be made with the unaided eye(normal spectacles excepted).
TABLE4Limiting Number of Test Specimens for Coating Tests
Nominal Diameter,in.
Maximum Number of Specimens to be Tested for2Cycles in180mL of Acid Solution
0.460to0.141,incl2 Under0.141to0.0851,incl4 Under0.0851to0.0501,incl6 Under0.0501to0.0381,incl10 Under0.0381to0.0301,incl12 Under0.0301to0.0030,incl
14
7.Inspection
7.1General (Explanatory Note 8and Note 9)—Unless otherwi specified in the contract or purchar order,the manufacturer shall be responsible for the performance of all inspection and test requirements specified.
7.1.1All inspections and tests shall be made at the place of manufacture unless otherwi especially agreed upon between the manufacturer and the purchar at the time of purcha.7.1.2The manufacturer shall afford the inspector reprent-ing the purchar all reasonable manufacturer’s facilities to satisfy him that the material is being furnished in accordance with this specification.
7.1.3Unless otherwi agreed upon between the purchar and the manufacturer,conformance of the wire to the various requirements listed in Section 5shall be determined on samples taken from ea
ch lot of wire prented for acceptance.
7.1.4The manufacturer shall,if requested prior to inspec-tion,certify that all wire in the lot was made under such conditions that the product as a whole conforms to the requirements of this specification as determined by regularly made and recorded tests.
7.2Definitions Applicable to Inspection :
7.2.1lot (Explanatory Note 8)—any amount of wire of one type and size prented for acceptance at one time,such amount,however,not to exceed 25000lb (11350kg).
7.2.2sample —a quantity of production units (coils reels,and so forth)lected at random from the lot for the purpo of determining conformance of the lot to the requirements of this specification.
7.2.3specimen —a length of wire removed for test purpos from any individual production unit of the sample.
7.3Sample Size (Explanatory Note 9)—The number of production units in a sample shall be as follows:
7.3.1For elongation and resistivity determinations,the sample shall consist of four production units.For continuity and adherence of coating tests,the sample shall consist of eight production units.From each unit,one test specimen of suffi-cient length shall be removed for the performance of the required tests.
7.3.2For dimensional measurements,the sample shall con-sist of a quantity of production units shown in Table 5under the heading “First Sample.”
7.3.3For surface-finish inspection and for packaging in-spection (when specified by the purchar at the time of placing the order)the sample shall consist of a quantity of production units shown in Table 6.
8.Conformance Criteria (Explanatory Note 9)
孝敬长辈的作文8.1Any lot of wire,the samples of which comply with the conformance criteria of this ction,shall be considered as complying to the requirements of Section 5.Individual pro-duction units that fail to meet one or more of the requirements shall be rejected.Failure of a sample group from a lot to meet one or more of the following criteria shall constitute cau for rejection of the lot.The conformance criteria for each of the prescribed properties given in Section 5are as follows:
8.1.1Elongation —The lot shall be considered conforming if the average elongation of the four specimens is not less than the appropriate elongation value in Table 1plus    2.8%;however,any individual production unit,the specimen from which has an elongation less than the appropriate elongation value in Table 1,shall be rejected.
8.1.1.1The lot shall be considered to have failed to meet the elongation conformance criterion if the average of the four specimens is less than the elongation in Table 1plus 2.8%and the elongation of any of the individual specimens is less than the value in Table 1.
8.1.1.2If the average of the four specimens is less than the elongation in Table 1plus 2.8%and the elongation of each of the individual specimens is equal to or more than the value in Table 1,six additional specimens from six production units other than the four originally sampled shall be tested.The lot shall be considered conforming if the elongation of each of the ten specimens is not less than the appropriate elongation value in Table 1,and the average of the ten specimens is not less than that value plus 2.8%.The lot shall be considered to have failed to meet the elongation requirement if any of the ten specimens is less than the appropriate elongation value in Table 1or if the average of the ten specimens is less than that value plus 2.8%.8.1.2Resistivity —The electrical resistivity of each of the four specimens shall conform to the requirements of    5.2.
TABLE 5Sampling for Dimensional Measurements
Number of Units in Lot
First Sample
Second Sample
Number of Units in
Sample,n 1
Allowable Number of Defects in First Sample,c 1.
Number of Units in
Sample,n 2
n 1plus n 2
Allowable Number of Defects in Both Samples,c 2
龙骨散
1to 14,incl .15to 50,.51to 100,incl 19023421101to 200,incl 24046702201to 400,incl 290761053401to 800,incl 3301121454Over 800
34
116
150
4
TABLE 6Sampling for Surface Finish and Packaging Inspection
Number of Units in Lot Number of Units in
Sample,n
Allowable Number of Defective Units,
c
1to 30,incl all 031to 50,incl 30051to 100,incl 370101to 200,incl 400201to 300,incl 702301to 500,incl 1002501to 800,incl 1303Over 800
155
4
Failure to meet the requirements shall constitute failure to meet the resistivity conformance criterion.
8.1.3Dimensions—The dimensions of thefirst sample (Table5)shall conform to the requirements of5.3.If there are no failures,the lot conforms to this requirement.If there are failures,but the number of the does not exceed the allowable defect number c2(Table5)for the respective number of units in the sample,a cond sample equal to n2shall be taken and the total defects of the n1plus n2units shall not exceed the allowable defect number,c2.Failure to meet this requirement shall constitute failure to meet the dimensional conformance criterion.
8.1.4Continuity of Coating—The continuity of the coating of each of the eight specimens shall conform to the require-ments of  5.4.Failure of more than two specimens shall constitute failure to m
eet the continuity criterion.If not more than two specimens fail to meet the continuity criterion,eight additional specimens from the lot shall be tested,all of which shall conform to the continuity criterion.However,any indi-vidual production unit,the specimen from which failed to meet the continuity criterion,shall be rejected.
8.1.5Adherence of Coating—The adherence of the coating of each of the eight specimens shall conform to the require-ments of  5.5.Failure of more than two specimens shall constitute failure to meet the adherence criterion.If not more than two specimens fail to meet the adherence criterion,eight additional specimens from the lot shall be tested,all of which shall conform to the adherence criterion.However,any indi-vidual production unit,the specimen from which failed to meet the adherence criterion,shall be rejected.
8.1.6Surface Finish—The surfacefinish of the samples taken in accordance with Table6shall conform to the require-ments of5.7.The number of units in the sample showing surface defects not consistent with commercial practice shall not exceed the allowable defect number c,in Table6.Failure to meet this requirement shall constitute failure to meet the surface-finish conformance criterion.
8.1.7Packaging—Conformance to the packaging require-ments specified by the purchar shall be d
etermined in accordance with Table6.The number of units in the sample showing nonconformance to the requirement shall not exceed the allowable defect number,c,in Table6.Failure to meet this requirement shall constitute failure to meet the packaging conformance criterion.
9.Density(Explanatory Note10)
9.1For the purpo of calculating linear densities,cross ctions,etc.,the density of the copper shall be taken as8.89 g/cm3(0.32117lb/in.3)at20°C.
10.Packaging and Shipping
10.1Package sizes shall be agreed upon by the manufac-turer and the purchar in the placing of individual orders. 10.2The tinned wire shall be protected against damage in ordinary handling and shipping.
11.Keywords
11.1tinned annealed copper wire;tinned copper electrical wire;tinned soft copper wire
EXPLANATORY NOTES
N OTE1—It is necessary that the coating of tin on the wire be continuous.The test in the sodium polysulfide is for the purpo of determining whether or not the wire carries a continuous envelope of pure tin.The thickness of the tin coating is necessarily varied.Under the same conditions of tinning,the coating on all sizes of wire,excepting onfine wire,is approximately the same.The coating onfine wire is in general relatively heavier than that on coar wire.It is not,therefore,correct to apply a larger number of cycles in the test on coar wire than is applied tofine wire.It is probable that one cycle of the dip test would be sufficient to discover defects in tinned wire,but in order to make certain that no partially covered spots may escape attention,provision has been made for two cycles.It has been found that the tin coating on copper wire consists of two parts,an envelope of pure tin on the outside,with an intermediate layer of copper-tin alloy.This tin alloy,as well as the amount of tin prent,has an effect on the resistivity of the wire.Since the relative amount of tin coating and alloy is greater on the small wire than it is on the coarr wire,the resistivity of the wire increas as the size decreas. This also accounts for the decrea in elongation due to tinning soft wire. N OTE2—The values of the wire diameters in Table1are given to the nearest0.0001in.and correspond to the standard sizes given in Specifi-cation B258.The u of gage numbers to specify wire sizes is not recognized in this specification becau of the possibility of confusion.An excellent discussion of wire gages and related subjects is contained in NBS Handbook100of the National Bureau of Standards.
N OTE3—Other tests than tho provided in this specification have been considered at various times,such as twist tests,wrap tests,and so forth.It is the opinion of the committee that twist tests on soft wire rve no uful purpo and that wrap tests,other than that provided for in6.5,which is a test for adhesion,are likewi undesirable and inconclusive as to results and significance.
N OTE4—“Resistivity”is ud in place of“percentage conductivity.”The value of0.15328V·g/m2at20°C is the international standard for the resistivity of annealed copper equal to100%conductivity.This term means that a wire1m in length and weighing1g would have a resistance of0.15328V.This is equivalent to a resistivity value of875.20 V·lb/mile2,which signifies the resistance of a wire1mile in length weighing1lb.It is also equivalent,for example,to1.7241µV/cm of length of a bar1cm2in cross ction.A complete discussion of this subject is contained in NBS Handbook100of the National Bureau of Standards.The prence of tin and of copper-tin alloy in the coating of the wire increas the resistance of thefinished wire as mentioned in Note1. Relationships that may be uful in connection with the values of resistivity prescribed in this specification are as shown in Table7,each column containing equivalent expressions at20°C.
N OTE5—In general,tested values of tensile strength are incread and tested values of elongation are reduced with increa of speed of the moving head of the testing machine in the tension testing
of copper wire. In the ca of tests on soft or annealed copper wire,however,the effects of speed of testing are not pronounced.Tests of soft wire made at speeds of moving head,which under no-load conditions are not greater than12 in./min,do not alter thefinal results of tensile strength and elongation determinations to any practical extent.
N OTE6—Caution:Consideration should be given to toxicity and flammability when lecting solvent
cleaners.

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