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Welding Electrodes and Rods Classification Specification, Exercises of Materials science

The requirements for the classification of low alloy steel electrodes and rods for gas metal arc welding, gas tungsten arc welding, and plasma arc welding. It includes chemical composition requirements, tension test requirements, and impact test requirements for various types of electrodes and rods.

Typology: Exercises

2011/2012

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SPECIFICATION FOR LOW-ALLOY STEEL
ELECTRODES AND RODS FOR GAS SHIELDED ARC
WELDING
SFA-5.28
(Identical with AWS Specification A5.28-96.)
1. Scope
This specification prescribes requirements for the
classification of low alloy steel electrodes (solid, com-
posite stranded, and composite metal cored) and rods
(solid) for gas metal arc welding (GMAW), gas tungsten
arc welding (GTAW), and plasma arc welding (PAW).
PART A GENERAL REQUIREMENTS
2. Classification
2.1 The solid electrodes (and rods) covered by this
specification are classified according to the chemical
composition of the electrode, as specified in Table 1,
and the mechanical properties of the weld metal, as
specified in Tables 3 and 4. The composite metal cored
and stranded electrodes covered by this specification
are classified according to the chemical composition
and mechanical properties of the weld metal, as specified
in Tables 2, 3, and 4, and the shielding gas employed.
2.2 Electrodes and rods under one classification shall
not be classified under any other classification in this
specification, except that ER80S-D2 may also be classi-
fied as ER90S-D2, provided that classification require-
ments for both are met.
2.3 The welding electrodes and rods classified under
this specification are intended for gas shielded arc
welding, but that is not to prohibit their use with any
other process (or any other shielding gas or combination
of shielding gases) for which they are found suitable.
565
3. Acceptance
Acceptance
1
of the electrodes and rods shall be in
accordance with the provisions of ANSI /AWS A5.01,
Filler Metal Procurement Guidelines.
2
4. Certification
By affixing the AWS specification and classification
designations to the packaging or the classification to
the product, the manufacturer certifies that the product
meets the requirements of this specification.
3
5. Units of Measure and Rounding-Off
Procedure
5.1 U.S. customary units are the standard units of
measure in this specification. The SI units are given
as equivalent values to the U.S. customary units. The
standard sizes and dimensions in the two systems are
not identical and, for this reason, conversion from a
standard size or dimension in one system will not
always coincide with a standard size or dimension in
the other. Suitable conversions, encompassing standard
sizes of both, can be made, however, if appropriate
tolerances are applied in each case.
1
See Section A3, Acceptance (in the Annex), for further information
concerning acceptance, testing of the material shipped, and ANSI⁄
AWS A5.01, Filler Metal Procurement Guidelines.
2
AWS Standards can be obtained from the American Welding
Society, 550 N.W. LeJeune Road, Miami, FL 33126.
3
See Section A4, Certification, (in the Annex) for further information
concerning certification and the testing called for to meet this
requirement.
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1. classification of low alloy steel electrodes (solid, com-posite stranded, and composite metal cored) and rods(solid) for gas metal arc welding (GMAW), gas tungstenarc welding (GTAW), and plasma arc welding (PAW). PART A — GENERAL REQUIREMENTS2.ELECTRODES AND RODS FOR GAS SHIELDED ARC This ScopeClassification specification SPECIFICATION FOR LOW-ALLOY STEEL prescribes requirements(Identical with AWS Specification A5.28-96.) WELDING for the^ SFA-5.

specification are classified according to the chemicalcomposition of the electrode, as specified in Table 1,and the mechanical properties of the weld metal, asspecified in Tables 3 and 4. The and stranded electrodes are classified according to the chemical compositionand mechanical properties of the weld metal, as specifiedin Tables 2, 3, and 4, and the shielding gas employed.not be classified under any other classification in thisspecification, except that ER80S-D2 may also be classi-fied as ER90S-D2, provided that classification require-ments for both are met.thiswelding, but that is not to prohibit their use with anyother process (or any other shielding gas or combinationof shielding gases) for which they are found suitable. 2.1 2.2 2.3 specification^ Electrodes and rods under one classification shallTheThe welding electrodes and rods classified under^ solid electrodes are intended covered by this specification^ (and rods) covered by this composite metal cored for gas shielded arc 565^ 3. accordance with the provisions of ANSI /AWS A5.01,^ Filler Metal Procurement Guidelines.^ 4. designations to the packaging or the classification tothe product, the manufacturer certifies that the productmeets the requirements of this specification.^ 5. measure in this specification. The SI units are givenas equivalent values to the U.S. customary units. Thestandard sizes and dimensions in the two systems arenot identical and, for this reason, conversion from astandardalways coincide with a standard size or dimension inthe other. Suitable conversions, encompassing standardsizes of both, can be made, however, if appropriatetolerances are applied in each case. 1 concerning acceptance, testing of the material shipped, and ANSI ⁄AWS A5.01, 2 Society, 550 N.W. LeJeune Road, Miami, FL 33126. 3 concerningrequirement. See Section A3, Acceptance (in the Annex), for further informationAWSSee Section A4, Certification, (in the Annex) for further information^^ Acceptance^ By affixing the AWS specification and classification 5.1 AcceptanceCertificationUnits of Measure and Rounding-OffProcedure U.S. customary units are the standard units ofStandards sizecertification Filler Metal Procurement Guidelines. 1 orof the electrodes and rods shall be incan dimension beand obtained the testing infrom one calledthe 2 systemAmerican for to^3 will meetWelding notthis

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SFA-5.28 1998 SECTION II

TABLE 1CHEMICAL COMPOSITION REQUIREMENTS FOR SOLID ELECTRODES AND RODSa,bWeight Percent

Other AWS^ UNS^

Elements c^ d^ Classification NumberC^ Mn^ Si^ P^ S^

e^ Ni Cr Mo V Ti Zr Al CuTotalCarbon-Molybdenum Steel Electrodes and Rods ER70S-A1^ K11235^ 0.12^ 1.30^ 0.30–0.70^ 0.025^ 0.^

0.20^ —^ 0.40–0.65^ —^ —^ —^ —^ 0.35^ 0.50 Chromium-Molybdenum Steel Electrodes and Rods ER80S-B2^ K20900^ 0.07–0.12^ 0.40–0.70^ 0.40–0.70^ 0.025^ 0.^

0.20^ 1.20–1.50^ 0.40–0.65^ —^ —^ —^ —^ 0.35^ 0.

ER70S-B2L^ K20500^ 0.05^ 0.40–0.70^ 0.40–0.70^ 0.025^ 0.^

0.20^ 1.20–1.50^ 0.40–0.65^ —^ —^ —^ —^ 0.35^ 0.

ER90S-B3^ K30960^ 0.07–0.12^ 0.40–0.70^ 0.40–0.70^ 0.025^ 0.^

0.20^ 2.30–2.70^ 0.90–1.20^ —^ —^ —^ —^ 0.35^ 0.

ER80S-B3L^ K30560^ 0.05^ 0.40–0.70^ 0.40–0.70^ 0.025^ 0.^

0.20^ 2.30–2.70^ 0.90–1.20^ —^ —^ —^ —^ 0.35^ 0.

f^ ER80S-B6S50280^ 0.10^ 0.40–0.70^ 0.50^ 0.025^ 0.^

0.6^ 4.50–6.00^ 0.45–0.65^ —^ —^ —^ —^ 0.35^ 0.

g^ ER80S-B8 S50480^ 0.10^ 0.40–0.70^ 0.50^ 0.025^ 0.^

0.5^ 8.00–10.5^ 0.8–1.2^ —^ —^ —^ —^ 0.35^ 0.

h,i^ ER90S-B9 S50482^ 0.07–0.13^ 1.25^ 0.15–0.30^ 0.010^ 0.^ 1.00^ 8.00–9.50^ 0.80–1.10^ 0.15–0.25^ —^ —^ 0.04^ 0.20^ 0.50 Nickel Steel Electrodes and Rods ER80S-Ni1^ K11260^ 0.12^ 1.25^ 0.40–0.80^ 0.025^ 0.025^ 0.80–1.

0.15^ 0.35^ 0.05^ —^ —^ —^ 0.35^ 0.

ER80S-Ni2^ K21240^ 0.12^ 1.25^ 0.40–0.80^ 0.025^ 0.025^ 2.00–2.

—^ —^ —^ —^ —^ —^ 0.35^ 0.

ER80S-Ni3^ K31240^ 0.12^ 1.25^ 0.40–0.80^ 0.025^ 0.025^ 3.00–3.

—^ —^ —^ —^ —^ —^ 0.35^ 0.50 Manganese-Molybdenum Steel Electrodes and Rods j ER80S-D2K10945^ 0.07–0.12^ 1.60–2.10^ 0.50–0.80^ 0.025^ 0.^

0.15^ —^ 0.40–0.60^ —^ —^ —^ —^ 0.50^ 0.

ER90S-D2^ Other Low-Alloy Steel Electrodes and Rods ER100S-1^ K10882^ 0.08^ 1.25–1.80^ 0.20–0.55^ 0.010^ 0.010^ 1.40–2.

0.30^ 0.25–0.55^ 0.05^ 0.10^ 0.10^ 0.10^ 0.25^ 0.

ER110S-1^ K21015^ 0.09^ 1.40–1.80^ 0.20–0.55^ 0.010^ 0.010^ 1.90–2.

0.50^ 0.25–0.55^ 0.04^ 0.10^ 0.10^ 0.10^ 0.25^ 0.

ER120S-1^ K21030^ 0.10^ 1.40–1.80^ 0.25–0.60^ 0.010^ 0.010^ 2.00–2.

0.60^ 0.30–0.65^ 0.03^ 0.10^ 0.10^ 0.10^ 0.25^ 0.

ERXXS-G^ —^

kNot Specified 566 NOTES:a.^ The filler metal shall be analyzed for the elements for which values are shown in this table. If the presence of other elements is indicated in the course of this work, the amount of those elements shallbe determined to ensure that their total (excluding iron) does not exceed the limits specified for “Other Elements, Total.”b.^ Single values are maximum.c.^ The suffixes B2, Ni1, etc., designate the chemical composition of the electrode and rod classification.d.^ SAE/ASTM Unified Numbering System for Metals and Alloys.e.^ Copper due to any coating on the electrode or rod plus the copper content of the filler metal itself, shall not exceed the stated limit.f.^ Similar to former class ER502 in AWS Specification A5.9-81.g.^ Similar to former class ER505 in AWS Specification A5.9-81.h.^ Niobium (Columbium) 0.02–0.10%i.^ Nitrogen 0.03–0.07%j.^ This composition was formerly classified E70S-1B in AWS Specification A5.18-69.k.^ In order to meet the requirements of the “G” classification, the electrode must have a minimum of one or more of the following: 0.50 percent nickel, 0.30 percent chromium, or 0.20 percentmolybdenum. Composition shall be reported; the requirements are those agreed to by the purchaser and supplier.docsity.com

A99 SFA-5.28 ER70S-B2LER70C-B2LER70S-A1ER80S-B2E80C-B2ER80S-B3LE80C-B3LER90S-B3E90C-B3ER80S-B6ER80S-B8ER90S-B9E70C-Ni2ER80S-Ni1E80C-Ni1ER80S-Ni2E80C-Ni2ER80S-Ni3E80C-Ni3 ClassificationAWS f^ fff Argon/1–5% OArgon/1–5% O Shielding Gas Argon/5% O 2 a 2 2 75 00080 00080 00090 00080 00090 00070 00080 00080 000 Tensile Strengthpsi(minimuim) TENSION TEST REQUIREMENTS MPa 515550550620550620480550550 1998 SECTION II TABLE 3 58 00068 00068 00078 00068 00060 00058 00068 00068 000 psiYield Strength(minimum) MPa 400470470540470410400470470 Elongation(minimum)Percent 191917171716242424 As-Welded Condition PWHTPWHTPWHT Testing c c c

ER80S-D2ER90S-D2E90C-D2ER100S-1ER110S-1ER120S-1ER70S-GE70C-GER80S-GE80C-GER90S-GE90C-GER100S-GE100C-GER110S-GE110C-GER120S-GE120C-GNOTES:a.b.c.d. The use of a particular shielding gas for classification purposes shall not be construed to restrict the use of shielding gas mixtures. A fillermetal tested with other gas blends, such as Argon/OClassification with other gas blends shall be as agreed upon between the purchaser and supplier.Yield strength at 0.2% offset and elongation in 2 in. (51 mm) gage length.Postweld heat-treated condition in accordance with Table 7.Shielding gas shall be as agreed to between purchaser and supplier. Argon/1–5% OArgon/2% OCO(d)(d)(d)(d)(d)(d) 2 2 2 100 000110 000120 000100 000110 000120 00080 00090 00070 00080 00090 000 2 or Argon/CO 550620690760830480550620690760830 105 000 2 68 00078 00088 00095 000 may result in weld metal having different strength and elongation.(e)(e)(e)(e)(e)(e) 470540610660730 (e)(e)(e)(e)(e)(e) (e)(e)(e)(e)(e)(e) 1717161514 As-WeldedAs-WeldedAs-Welded(e)(e)(e)(e)(e)(e)

e.f. Not specified (As agreed to between purchaser and supplier).These classifications were previously ER80S-B2, E80C-B2, ER90S-B3L, and E90C-B3L respectively in AWS A5.28–79. The strength levelshave been adjusted downward as shown, in order to accurately reflect the capability of the classification’s chemical composition ranges. (^568) docsity.com

Classification ER70S-A1ER70S-B2LE70C-B2LER80S-B2E80C-B2ER80S-B3LE80C-B3LER90S-B3E90C-B3ER80S-B6ER80S-B8ER90S-B9ER80S-Ni1E80C-Ni1ER80S-Ni2E70C-Ni2E80C-Ni2ER80S-Ni3E80C-Ni3 AWS^ IMPACT TEST REQUIREMENTS 20 ft·lbf at −100°F(27 J @ −73°C)20 ft·lbf at −50°F(27 J @ −46°C)20 ft·lbf at −80°F(27 J @ −62°C) Average Impact Strength Not Required^ TABLE 4(minimum) PART C — SPECIFICATIONS FOR WELDING RODS, ^ a^ ELECTRODES, AND FILLER METALS As-Welded ConditionTesting PWHTPWHT— b b^ SFA-5.

ER80S-D2ER90S-D2E90C-D2ER100S-1ER110S-1ER120S-1ERXXXS-GEXXC-GNOTES:a.b.this specification, an observed or calculated value shallbeyield strength, and to the “nearest unit” in the last (^) 5.2 Both the highest and lowest of the five test values obtained shallbe disregarded in computing the impact strength.maining three values shall equal or exceed 20 ft-lbf (27 J); oneof the three remaining values may be lower than 20 ft-lbf (27 J)but not lower than 15 ft-lbf (20 J). The average of the three shallnot be less than the 20 ft-lbf (27 J) specified.maining three values shall equal or exceed 50 ft-lbf (68 J); oneof the three remaining values may be lower than 50 ft-lbf (68 J)but not lower than 40 ft-lbf (54 J). The average of the three shallnot be less than the 50 ft-lbf (68 J) specified.Postweld heat treated in accordance with Table 7.rounded to the nearest 1000 psi for tensile andFor classifications requiring 20 ft-lbf (27 J); Two of the re-For classifications requiring 50 ft-lbf (68 J): Two of the re- For the purpose of determining conformance with 20 ft·lbf at −20°F(27 J @ −29°C)50 ft·lbf at −60°F(68 J @ −51°C)purchaser and supplierAs agreed between As-WeldedAs-Welded— right-handlimiting value for other quantities in accordance withthe rounding-off method given in ASTM E29, place of figures used in expressing Recom- the 569

mended Practice for Using Significant Digits in TestData to Determine Conformance with Specifications. PART B — TESTS, PROCEDURES, ANDREQUIREMENTS6. specified in Table 5. The purpose of these tests is todetermine the chemical composition, the mechanicalproperties, and soundness of the weld metal. The basemetal for the weld test assemblies, the welding andtestingrequired are given in Sections 8 through 12.Section 13, Diffusible Hydrogen Test, is not requiredfor classification [see note (a) of Table 5]. 7. that test shall be repeated twice. The results of bothretests shall meet the requirement. Specimens for retestmay be taken from the original test assembly or fromone or two new test assemblies. For chemical analysis, (^) 6.1 6.2 If the results of any test fail to meet the requirement, Summary of TestsRetest TheTheprocedures testsoptional required to testbe foremployed,for diffusibleeach classificationand hydrogen the results arein 4 retest need be only for those specific elements thatfailed to meet the test requirement. If the results ofone or both retests fail to meet the requirement, thematerial under test shall be considered as not meeting therequirements of this specification for that classification.In the event that, during preparation or after completionof any test, it is clearly determined that prescribed orproper procedures were not followed in preparing theweld test assembly or test specimen(s), or in conductingthe test, the test shall be considered invalid, withoutregard to whether the test was actually completed, orwhether test results met, or failed to meet, the require-ment,prescribed procedures. In this case, the requirement fordoubling the number of test specimens does not apply. 8. two may be required (depending on the electrode —solid as opposed to composite — and the manner inwhich the sample for chemical analysis is taken), asspecified in Table 5. They are as follows: (^4) for Testing and Materials (ASTM), 100 Barr Harbor Drive, Consho-hocken, PA 19428-2959. (^) ASTM specifications may be obtained from the American Society (^) 8.1 (^) Weld Test Assemblies At least one weld test assembly is required, andthat test shall be repeated, following proper docsity.com

ties and soundness of the weld metal for both compositeand solid electrodesthe weld metal from composite stranded and compositemetal cored electrodescomposite electrodes may be taken from the reducedsectionspecimen or from the corresponding location in thegroove weld in Fig. 1, thereby avoiding the need tomake a weld pad. Alternatively, the sample from thegroove weld may be taken from any location in theweld metal above the tension test specimen. In caseof dispute, the weld pad in Fig. 2 shall be the refereemethod.as prescribed in 8.3, 8.4, and 8.5. The base metal foreach assembly shall be as required in Table 6, andshall meet the requirements of the ASTM specificationshown there, or an equivalent specification. Testing ofthe assembly shall be as prescribed in 9.2, 9.3, andSections 10 through 12.^ (1) (2) The sample for chemical analysis of weld metal from 8.2^ The groove weld in Fig. 1 for mechanical proper-The weld pad in Fig. 2 for chemical analysis ofPreparation of each weld test assembly shall be of the fractured all-weld-metalPART C — SPECIFICATIONS FOR WELDING RODS,ELECTRODES, AND FILLER METALS tension test^ SFA-5. be prepared and welded as specified in Fig. 1, usingbase metal of the appropriate type specified in Table6, and the preheat and interpass temperature specifiedin Table 7. The electrode used shall be 0.045 in. (1.1mm) ormanufacturer produces that is closest to one of these,if these sizes are not produced).shall be restrained (or preset) during welding to preventwarpage in excess of 5 degrees. An assembly that haswarpeddiscarded. It shall not be straightened. The test assemblyshall be tack welded, and welding shall begin at thepreheat temperature specified in Table 7.the remainder of the weld. Should it be necessary tointerrupt welding, the assembly shall be allowed tocool in still air to room temperature. The assemblyshall be preheated to the temperature shown in Table7 before welding is resumed. When welding has beencompleted and the assembly has cooled, the assemblyshall be prepared and tested as specified in Sections10,treated condition, as specified in Tables 3 and 4.^ 8.3 Groove Weld Welding shall be in the flat position, and the assemblyThis interpass temperature shall be maintained for 11, and 8.3.1 more 1^ ⁄ 16 For all classifications, a test assembly shall in. (1.6 mm) size (or the size that the (^) 12 in the as-welded or postweld heat-than 5 degrees from plane shall be postweld heat-treated before removal of mechanical test^ 8.3.2^ When required, the test assembly shall be 571

specimens. This postweld heat treatment may be doneeither before or after the radiographic examination.not higher than 600°F (320°C) when the test assemblyis placed in it. The heating rate, from that point tothe specified holding temperature in Table 7, shall notexceed 400°F per hour (220°C per hour).at the temperature specified in Table 7 for 1 hour (−0,+15 minutes).been completed, the assembly shall be allowed to coolin the furnace to a temperature below 600°F (320°C)at a rate not exceeding 350°F (190°C) per hour. Theassembly may be removed from the furnace at anytemperature below 600°F (320°C) and allowed to coolin still air to room temperature. Testing of the assemblyshall be as specified in Sections 10 through 12.composite stranded and composite metal cored elec-trodes as shown in Fig. 2, except when, as permittedin 8.1, the sample for analysis is taken from the grooveweld (Fig. 1) or the fractured tension test specimen. 8.4 Weld Pad. 8.3.2.1 8.3.2.2 8.3.2.3 The furnace shall be at a temperatureThe test assembly shall be maintainedWhen the one hour holding time has A weld pad shall be prepared using Base metal of any convenient size which will satisfythe minimum requirements of Fig. 2, and is of a typespecified in Table 6, shall be used as the base for theweld pad. The surface of the base metal on which thefiller metal is deposited shall be clean. The pad shallbe welded in the flat position with multiple layers toobtain undiluted weld metal (4 layers minimum thick-ness). The electrode size shall be 0.045 in. (1.1 mm)orproduces that is closest to one of these, if these sizesare not produced. The preheat temperature shall notbe less than 60°F (16°C) and the interpass temperatureshall not exceed that specified in Table 7. Any slagshall be removed after each pass. The pad may bequenched in water between passes (temperature of thewater is not specified). The dimensions of the completedpad shall be as shown in Fig. 2. Testing of this assemblyshall be as specified in 9.2 and 9.3. The results shallmeet the requirements of 9.4. 9. prepared for chemical analysis. Solid filler metal, whenanalyzed for elements that are present in a coating(copper flashing, for example), shall be analyzed without (^) 9.1 (^1) ⁄ (^16) Chemical Analysis (^) A sample of the solid electrode or rod shall bein. (1.6 mm), or the size that the manufacturer removing the coating. When the filler metal is analyzeddocsity.com

SFA-5.28 1998 SECTION II

FIG. 1 GROOVE WELD TEST ASSEMBLY FOR MECHANICAL PROPERTIES AND SOUNDNESS (^572) docsity.com

SFA-5.28AWS Classification ER70S-B2LE70C-B2LER80S-B2E80C-B2ER80S-B3LE80C-B3LER90S-B3E90C-B3ER80S-B6ER80S-B8ER90S-B9ER80S-Ni1E80C-Ni1E70C-Ni2ER80S-Ni2 A203 Grade A or B, or HY-80 steelA203 Grade A or B or HY-80 steelin accordance with MIL-S-16216 Base Metal ASTM Standard A516 Grade 60, 65, or 70 BASE METAL FOR TEST ASSEMBLIES A537 Class 1 or 2A387 Grade 11A387 Grade 22A387 Grade 91A387 Grade 5A387 Grade 91998 SECTION II TABLE 6 a K02100, K02403, or K02700K12437, K21703, or K22103K22103, K21703, or J42015 Base Metal UNS Number K11789K21590S50200S50400S50460J42015 b

E80C-Ni2ER80S-Ni3E80C-Ni3ER70S-A1ER80S-D2E90C-D2ER90S-D2ER100S-1ER100S-GE100C-GER110S-1ER110S-GE110C-GER120S-1ER120S-GE120C-GERXXS-GEXXC-GNOTES:a. For any weld metal classification in this specification, ASTM A36, A285 Grade C, A515 Grade 70, or A516 Grade 70 may be used. In thatb. ASTM/SAE Unified Numbering System for Metals and Alloys.case, the groove faces and the contacting face of the backing shall be buttered, as shown in Figure 1, using the electrode being classified oran electrode of the same weld metal composition as that specified for the electrode being tested, or using an electrode of the specifiedcomposition classified in another AWS low-alloy steel filler metal specification. Alternately, for the indicated weld metal classification, thecorresponding base metals may be used for weld test assemblies without buttering. In case of dispute, buttered A36 steel shall be the refereematerial. A203 Grade D or E or HY-80 steelin accordance with MIL-S-16216in accordance with MIL-S-16216in accordance with MIL-S-16216ASTM A36, A285 Grade C,HY-80 or HY100 steelA515 Grade 70, orA516 Grade 70See note a K31718 or K32018J42015 or J42240K02600,K03101,K02700J

(^574) docsity.com