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SPECIFICATION FOR ZIRCONIUM AND ZlRCONIUM
ALLOY WELDING ELECTRODES AND RODS
SFA-5.
(Identical with AWS Specification A5.24-90)
1. Scope
This specification prescribes requirements for the classification of zirconium and zirconium alloy elec- trodes and rods for plasma arc, gas metal arc, and gas tungsten arc welding.
PART A — GENERAL REQUIREMENTS
2. Classification
2.1 The welding materials covered by this specifica- tion are classified according to the chemical composition of the filler metal as specified in Table 1.
2.2 Material classified under one classification shall not be classified under any other classification of this specification.
2.3 The materials classified under this specification are intended for plasma arc, gas metal arc, and gas tungsten arc welding, but that is not to prohibit their use with any other process for which they are found suitable.
3. Acceptance
Acceptance^1 of the material shall be in accordance with the provisions of ANSI /AWS A5.01, Filler Metal Procurement Guidelines.^2
(^1) See A3 (in the Appendix) for further information concerning accept- ance, 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, P.O. Box 351040, Miami, Florida 33135.
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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.
5.2 For the purpose of determining conformance with this specification, an observed or calculated value shall be rounded to the nearest unit in the last right-hand place of figures used in expressing limiting values in accordance with the rounding-off method given in ANSI /AWS A1.1, Metric Practice Guide for the Weld- ing Industry.
(^3) See A4 (in the Appendix) for further information concerning Certifi- cation and the testing called for to meet this requirement.
SFA-5.24 1998 SECTION II
TABLE 1 CHEMICAL COMPOSITION REQUIREMENT AND ZIRCONIUM AND ZIRCONIUM ELECTRODES AND RODS
Chemical Composition, Wt Percent (1)
AWS UNS Zirconium + Iron + Classification Number (2)^ Hafnium Hafnium Chromium Tin Oxygen Hydrogen Nitrogen Carbon Columbium
ERZr2 R60702 99.01 min 4.5 0.20... 0.16 0.005 0.025 0....
0.20 1. ERZr3 R60704 97.5 min 4.5 to to 0.16 0.005 0.025 0.... 0.40 2.
ERZr4 R60705 95.5 min 4.5 0.20... 0.16 0.005 0.025 0.05 to
NOTES (1) Single values are maximum, except as noted. (2) ASTM/SAE Unified Numbering System for Metals and Alloys. Document may be obtained from SAE, Inc., 400 Commonwealth Drive, Warrendale, Pennsylvania 15096-0001. (3) Analysis of the interstitial elements C, O, H and N shall be conducted on samples of filler metal taken after the filler metal has been reduced to its final diameter and all processing operations have been completed. Analysis of the other elements may be conducted on these same samples or it may have been conducted on samples taken from the ingot or the rod stock from which the filler metal is made. In case of dispute, samples from the finished filler metal shall be the referee method.
PART B — TESTS, PROCEDURES, AND
REQUIREMENTS
6. Summary of Tests
Chemical analysis of the filler metal (or, as an alternative for part of the analysis, the stock from which the filler metal is made — see Note (3) to Table
- is the only test required for classification of a product under this specification.
7. Retest
If the result of any test fails to meet its requirement, that test shall be repeated twice. The results of both retests shall meet the requirement. Samples for retest may be taken from the original test sample or from one or two new samples. Retest need be only for those specific elements that failed to meet the test requirement.
8. Chemical Analysis
8.1 A sample of the filler metal, or the rod stock from which it was made, shall be prepared for chemical analysis.
8.2 The sample shall be analyzed by accepted analyti- cal methods. The referee method shall be ASTM Method
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E 146, Chemical Analysis of Zirconium and Zirconium Alloys.^4
8.3 The results of the analysis shall meet the require- ments of Table 1, for the classification of filler metal under test.
PART C — MANUFACTURE,
IDENTIFICATION, AND PACKAGING
9. Method of Manufacture The welding electrodes and rods classified according to this specification may be manufactured by any method that will produce material that meets the requirements of this specification. 10. Standard Sizes Standard sizes for filler metal in the different package forms (straight lengths, coils with support, coils without support, and spools) are shown in Table 2.
(^4) ASTM standards can be obtained from the American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylva- nia 19103.
SFA-5.24 1998 SECTION II
TABLE 3 STANDARD PACKAGE DIMENSIONS AND WEIGHTS
Diameter Filler Metal Net Weight Size (1)^ of Package (1) (2)^ Width (3)^ Inside (4)^ Outside
in. mm lb. kg in. mm in. mm in. mm
Straight Lengths
(^1) ⁄ 16 1.6 10 4................... through through 50 23.................. (^3) ⁄ 16 4.
Coils With Support and Coils Without Support 1 ⁄ 16 1.6 2 1 ⁄ 2 65 13 5 ⁄ 8 345 through through 25 11 or or 12 6 1 ⁄ 8 305 6 3 15 1 ⁄ 8 400 (^3) ⁄ 16 4.8 50 23 4 5 ⁄ 8 120 17 420 60 27 4 5 ⁄ 8 120 17 1 ⁄ 2 430
Spools 0.020 0.5 1 0.5 See Fig.1...... See Fig. through through 5 2.2 See Fig.2...... See Fig. (^1) ⁄ 16 1.6 15 6.8 See Fig.2...... See Fig.
NOTES: (1) Sizes, dimensions, and weights other than these shall be as agreed to by the purchaser and the supplier. (2) Actual net weight of the filler metal in each package shall be within 10 percent of the standard net weight shown. (3) Width of coils and spools. (4) Inside diameter of the liner for coils with support, and of the coil itself, for coils without support.
14.4 Spools shall have the information securely af- fixed in a prominent location on the outside of one flange of the spool.
15. Packaging
Electrodes and rods shall be suitably packaged to ensure against damage during shipment and storage under normal conditions.
16. Marking of Packages
16.1 The following product information (as a mini- mum) shall be legibly marked so as to be visible from the outside of each unit package. (a) AWS specification and classification number (year of issue may be excluded); (b) Supplier’s name and trade designation; (c) Size and net weight; (d) Lot, control, or heat number.
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16.2 The following precautionary information (as a minimum) shall be prominently displayed in legible print on all packages of welding material, including individual unit packages enclosed within a larger package.
WARNING:
PROTECT yourself and others.
Read and understand this information.
FUMES AND GASES can be dangerous to your
health.
ARC RAYS can injure eyes and burn skin.
ELECTRIC SHOCK can kill.
O Before use read and understand the manufacturer’s instructions, Material Safety Data Sheets (MSDSs), and your employer’s safety practices. O Keep your head out of the fumes.
PART C — SPECIFICATIONS FOR WELDING RODS, ELECTRODES, AND FILLER METALS SFA-5.
FIG. 1 DIMENSIONS OF STANDARD 4 IN. (100 MM) SPOOLS
FIG. 2 DIMENSIONS OF STANDARD 12 IN. (300 MM) SPOOLS FOR 10 AND 25 LB (4.5 AND 11 KG) OF FILLER METAL 525
PART C — SPECIFICATIONS FOR WELDING RODS, ELECTRODES, AND FILLER METALS SFA-5.
Appendix
Guide to AWS Specification for Zirconium and Zirconium
Alloy Welding Electrodes and Rods
(This Appendix is not a part of ANSI /AWS A5.24-90, Specification for Zirconium and Zirconium Alloy Welding Electrodes and Rods, but is included for information purposes only.)
A1. Introduction
A1.1 The specification is intended to provide both the supplier and the purchaser of zirconium and zirco- nium alloy bare welding electrodes and rods with a means of product control and a basis of acceptance through mutually acceptable, sound, standard require- ments.
A1.2 This guide has been prepared as an aid to prospective users of zirconium and zirconium alloy filler metals included in the specification to determine the classification best suited for a particular application, with due consideration to the particular requirements for that application.
A2. Method of Classification
A2.1 The system of classification is similar to that used in other filler metal specifications. The letter “E” at the beginning of each designation indicates a welding electrode, and the letter “R” indicates a welding rod. Since these filler metals are used as welding electrodes in gas metal arc welding and as welding rods in gas tungsten arc welding, both letters are used. The letters “Zr” indicate that the filler metals have a zirconium base. The digits and letters that follow provide a means for identifying the nominal composition of the filler metal.
A3. Acceptance
Acceptance of all welding materials classified under this specification is in accordance with ANSI /AWS A5.01, Filler Metal Procurement Guidelines, as the
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Specification states. Any testing a purchaser requires of the supplier, for material shipped in accordance with this specification, shall be clearly stated in the purchase order, according to the provisions of ANSI /AWS A5.01. In the absence of any such statement in the purchase order, the supplier may ship the material with whatever testing the supplier normally conducts on material of that classification, as specified in Schedule F, Table 1, of the Filler Metal Procurement Guidelines. Testing in accordance with any other Schedule in that table must be specifically required by the purchase order. In such cases, acceptance of the material shipped will be in accordance with those requirements.
A4. Certification The act of placing the AWS specification and classi- fication designations on the packaging enclosing the product, or the classification on the product itself, constitutes the supplier’s (manufacturer’s) certification that the product meets all of the requirements of the specification. The only testing requirement implicit in this certifica- tion is that the manufacturer has actually conducted the tests required by the specification on material that is representative of that being shipped and that the material met the requirements of the specification. Rep- resentative material, in this case, is any production run of that classification using the same formulation. “Certification” is not to be construed to mean that tests of any kind were necessarily conducted on samples of the specific material shipped. Tests on such material may or may not have been conducted. The basis for the certification required by the specification is the
SFA-5.24 1998 SECTION II
classification test of “representative material” cited above, and the “Manufacturer’s Quality Assurance Pro- gram” in ANSI /A5.01, Filler Metal Procurement Guide- lines.
A5. Ventilation During Welding
A5.1 Five major factors govern the quantity of fumes in the atmosphere to which welders and welding operators are exposed during welding: (a) Dimensions of the space in which welding is done (with special regard to height of the ceiling); (b) Number of welders and welding operators work- ing in that space; (c) Rate of evolution of fumes, gases, or dust, ac- cording to the materials and process involved. (d) The proximity of the welders or welding operators to the fumes as they issue from the welding zone, and to the gases and dusts in the space in which they are working; (e) The ventilation provided in the space in which the welding is done.
A5.2 American National Standard Z49.1, Safety in Welding and Cutting (published by the American Weld- ing Society), discusses the ventilation that is required during welding and should be referred to for details. Attention is directed particularly to the section of that document on “Health Protection and Ventilation.”
A6. Welding Considerations
A6.1 Zirconium and zirconium alloys can be welded by gas tungsten arc, gas metal arc, plasma arc, and electron beam welding processes. Zirconium is a reactive metal and is sensitive to embrittlement by oxygen, nitrogen and hydrogen at temperatures above 1100°F (590°C). Consequently, the metal should be protected from atmospheric contamination. This can be provided by shielding the metal with high purity inert gas in air, in a chamber, or by a vacuum of 10−4^ torr or lower. During arc welding, the zirconium must be shielded from the atmosphere until it is cooled below about 1100°F (593°C). Adequate protection by auxiliary inert gas shielding should be provided when welding in air and for critical applications the welding should be done in a gas tight chamber thoroughly purged of air and filled with high purity inert gas. The zirconium metal should be free of heavy oxide and chemically clean prior to welding, as contamination from oxide, water, grease, and dirt will also cause embrittlement.
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Zirconium welding rods must be chemically clean and free of heavy oxide, absorbed moisture, grease, and dirt. The welding rod should be kept in the inert gas during welding and the oxide at the tip, formed upon cooling, must be removed before reusing the rod. Zirconium can be successfully fusion welded to titanium, tantalum, columbium (niobium), and vanadium although the weld metal will be stronger and less ductile than the base metals. Zirconium should not be fusion welded to other common structural alloys of copper, iron nickel, and aluminum as brittle zirconium intermetallic alloys are formed which produce extremely brittle welds.
A7. Description and Intended Use of Electrodes and Rods A7.1 The ERZr2 classification is a “commercially pure” zirconium. It produces weld metal having good strength and ductility. The tensile strength should be at least 55 000 psi (379 MPa). These electrodes and rods can be used to weld all of the zirconium alloys. A7.2 The ERZr3 classification contains tin as an alloying element. Tin increases the strength of the weld metal, yet allows it to retain good ductility. The strength should be at least 60 ksi (410 MPa). These electrodes and rods are intended only for welding UNS R zirconium alloy. Weld metal from ERZr3 filler metal may not resist corrosions as well as that from ERZr filler metal. A7.3 The ERZr4 classification contains columbium as an alloying element. It produces weld metal of good ductility with a tensile strength of at least 80 ksi ( MPa). These electrodes and rods are used only to weld UNS R60705 zirconium alloy. Weld metal from ERZr filler metal may not resist corrosion as well as that from ERZr2 filler metal.
A8. Special Tests It is recognized that supplementary tests may be required for certain applications. In such cases, tests to determine specific properties such as (corrosion resistance, scaling resistance, or strength at elevated temperatures or cryogenic temperatures) may be re- quired. ANSI /AWS A5.01, Filler Metal Procurement Guidelines contains provisions for ordering such tests. This section is included for the guidance of those who desire to specify such special tests. Those tests may be conducted as agreed upon between supplier and purchaser.
