SAE J1442-1993 HIGH-STRENGTH, HOT-ROLLED STEEL PLATES, BARS, AND SHAPES.pdf

SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. QUESTIONS REGARDING THIS DOCUMENT: (412) 772-8512 FAX: (412) 776-0243 TO PLACE A DOCUMENT ORDER; (412) 776-4970 FAX: (412) 776-0790 Copyright 1993 Society of Automotive Engineers, Inc. All rights reserved.Printed in U.S.A. SURFACE VEHICLE 400 Commonwealth Drive, Warrendale, PA 15096-0001 RECOMMENDED PRACTICE Submitted for recognition as an American National Standard J1442 REV. NOV93 Issued1984-06 Revised1993-11 Superseding J1442 DEC88 (R) HIGH-STRENGTH, HOT-ROLLED STEEL PLATES, BARS, AND SHAPES ForewordThis Document has not changed other than to put it into the new SAE Technical Standards board Format. 1.ScopeThis SAE Recommended Practice covers six levels of high strength carbon and high-strength low- alloy steel plates, bars, and shapes for structural use. The six strength levels are 290, 345, 415, 450, 485, and 550 MPa or 42, 50, 60, 65, 70, and 80 ksi minimum yield point. Different chemical compositions are used to achieve the specified mechanical properties. In some cases there are significant differences in chemical composition for the same strength level, depending on the fabricating requirements. Because the chemical compositions may vary significantly among the producers, despite the required mechanical properties being the same, it is important that the fabricator consult with the producer to determine the relative effects of the producer's composition on the forming, welding, and field service requirements. The products within the scope of this document include the following: a.PlatesFlat hot-rolled steel (cut length only) greater than 200 mm (8 in) wide and greater than 5.8 mm (0.230 in) thick, and greater than 1220 mm (48 in) wide and greater than 4.6 mm (0.179 in) thick. For sheet and strip products (less than 5.8 mm (0.230 in) thickness), refer to SAE J1392. b.BarsRounds, squares, and hexagons of all sizes (cut length only, flats 5.2 mm (0.203 in) and greater in thickness but not greater than 150 mm (6 in) wide, and flats greater than 5.8 mm (0.229 in) thick and over 150 mm (6 in) to 204 mm (8 in) wide. c.Structural ShapesHot-rolled flanged sections having at least one dimension of the cross section 75 mm (3 in) or greater. (Size groupings for tensile property classification are listed in ASTM A 6/A 6M Table A.) d.Bar Size ShapesHot-rolled flanged sections having a maximum dimension of the cross section less than 75 mm (3 in). 1.1IntroductionHigh-strength steel discussed in this SAE Recommended Practice involves hot-rolled plates, bars, structural shapes, and bar size shapes. The strength is achieved through chemical composition and rolling pratice; it is not achieved through quenching and tempering or additional rolling operations. SAE J1442 Revised NOV93 -2- 2.References 2.1Applicable PublicationsThe following publications form a part of the specification to the extent specified herein. 2.1.1ASTM PUBLICATIONSAvailable from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959. ASTM A 6/A 6MGeneral Requirements for Rolled Steel Plates, Shapes, Sheet Piling, and Bars of Structural Use ASTM A 370Standard Methods and Definitions for Mechanical Testing of Steel Products ASTM A 572/A 572MSpecification for High-Strength Low-Alloy Columbium-Vanadium Steels of Structural Quality ASTM A 588/A 588MSpecification for High-Strength Low-Alloy Structural Steel with 50 ksi (345 MPa) Minimum Yield Point to 4 in thick ASTM A 656/A 656MSpecification for Hot-Rolled Structural Steel, High-Strength Low-Alloy Plate with Improved Formability ASTM G 101Guide for Estimating the Atmospheric Corrosion Resistance of Low Alloy Steels 3.General InformationThe specific grades are identified by the minimum yield point expressed in MPa, that is 290, 345, 415, 450, 485, and 550 or in ksi, that is 42, 50, 60, 65, 70, and 80 ksi. They are further identified at some strength levels with the suffixes A, W, and F. Chemical composition and processing variables are the bases for the suffix differences. The A suffix generally identifies the relatively higher carbon compositions compared to the W and F suffix grades. Also, the A suffix grades specify a difference between the minimum yield point and the minimum tensile strength of at least 105 MPa or 15 ksi. Grades 290A, 345A, 415A, and 450A are similar to grades contained in ASTM A 572/A 572M. The W suffix identifies a grade with improved atmospheric corrosion resistance. The corrosion resistance of this steel in most environments is substantially better than that of carbon structural steels with or without copper addition. When properly exposed to the atmosphere, this steel can be used bare (unpainted) for many applications. For methods of estimating the atmospheric corrosion resistance of low-alloy steels, see ASTM G 101. The F suffix grades are the most formable grades in this practice. They are characterized by lower carbon content than the A and W suffix grades, and are normally made to killed steel fine grain and sulfide inclusion control practices. Due to the lower carbon content, the difference between the yield point and tensile strength is generally less than the difference in the A and W suffix grades. The F suffix grades, which normally are available only in Plates and Bar Size Flats, specify a difference between minimum yield point and minimum tensile strength of at least 70 MPa or 10 ksi although some producers use a chemical composition that provides differences of approximately 105 MPa or 15 ksi. It is important to note that these grades possess superior formability at their respective strength levels. The relatively smaller difference between the yield point and tensile strength does not lessen this high degree of formability. Grades 345F, 415F, 485F, and 550F are similar to grades contained in ASTM A 656/A 656M. When killed steel is required, the suffix K should follow the grade designation, 290AK (42AK), or 345AK (50AK), or 415AK (60AK). SAE J1442 Revised NOV93 -3- Because these steels are characterized by their special mechanical properties obtained in the as-rolled conditions, they are not intended for any heat treatment by the purchaser either before, during, or after fabrication. The fabricator should not subject these steels to such heat treatments without assuming responsibility for the resulting mechanical properties. For certain applications, these steels may be annealed, normalized, or stress relieved with some effect on the mechanical properties; it is recommended that prior to such heat treatments, the purchaser should consult the producer to determine the need for and the effect on mechanical properties. All grades and chemical compositions discussed in the practice are weldable despite the differences in carbon, manganese, and alloying addition. Because of the aforementioned variations in composition from one producer to another, it is advisable to discuss with the producers the features of their chemical composition relative to the various types of welding and any special consideration for each application. These steels, because of their high strength-to-weight ratio, are adapted particularly for use in mobile equipment and other structures where substantial weight savings are generally desirable. 4.Mechanical PropertiesThe mechanical properties of these steels are shown in Tables 1A and 1B. If thicknesses greater than those shown in the table are required, consultation with the producers regarding availability and characteristics is suggested. Present steel industry practice is to express the yield point of these grades rather than the yield strength. Such determination is by drop of beam or halt of the pointer method, autographic diagram method, or the total extension under load method as described in ASTM A 370. Unless otherwise specified, this procedure is acceptable for material supplied in this report, and the use of an extensometer is not required. It is suggested that any disagreement between the seller and purchaser over the yield point value of a given lot be resolved by the 0.2% offset or the 0.5% extension under load methods, also described in ASTM A 370. 5.Chemical CompositionThe chemical composition (heat analysis) of steel furnished to this practice shall conform to Table 2. Because the chemical compositions vary significantly among the producers despite the required mechanical properties being the same, it is advisable for the purchaser to discuss specific compositions with each producer, especially if welding, atmospheric corrosion, and/or forming are critical factors. The commonly used alloying elements are, in alphabetical order: chromium, columbium (niobium), copper, molybdenum, nickel, titanium, vanadium, and zirconium. Choice of, and limits for the alloying additions, other than those shown in Table 2, which are necessary to attain the required properties, may be specified by mutual agreement between purchaser and producer at the time of ordering. Once specified, they may not be changed without both parties' consent. 6.Suggested Bending PracticeThe suggested cold forming practice is to avoid bends with an inside radius less than that shown in Table 3. These minimum forming radii for 90-degree bends have been established by experience using press brake bending in a direction parallel to the direction of final rolling (“hard way“ bends). Should bending be accomplished across the direction of final rolling, slightly tighter radii could be used. Where design conditions permit, however, users are encouraged to utilize a slightly larger radius than that shown as an added safety factor. In any bending, it is presupposed that reasonably good forming practices will be used. It should be noted that all steel has a tendency to crack when bent on a sheared or gas cut edge. This is not to be considered a fault of the steel, but rather a function of the induced cold work or heat affect zone. Where bends are to be made on a sheared edge, best performance is attained when the shear burr is located on the inside of the bend. 7.Dimensional TolerancesStandard manufacturing tolerances for dimensions, as shown in the latest edition of ASTM A 6/A 6M shall apply. SAE J1442 Revised NOV93 -4- TABLE 1AMECHANICAL PROPERTIES(1)(2) - PLATES, BARS, BAR SIZE SHAPES 1.For plates wider than 610 mm (24 in), the test specimen is taken in the transverse direction. 2.Mechanical testing (location, number of tests, preparation, and method) is to be in accordance with the latest revision of ASTM A 6/A 6M. Grade Nominal Maximum Thickness mm Nominal Maximum Thickness in Yield Point(3) Minimum MPa 3.May be reported as yield strength as measured by the 0.2% offset or 0.5% extension under load method. Yield Point(3) Minimum ksi Tensile Strength(4)(5) Minimum MPa 4.Some applications may require a maximum tensile strength. In such cases, the following values must be determined from the producer for acceptance prior to issuing a purchase order. 5.Only one set of units apply to yield and tensile and the reported value should be based on the units of the purchase order. In addition only one set of elongation values (2 in or 8 in) need to be met and reported. Tensile Strength(4)(5) Minimum ksi Elongation(5)(6) Minimum % Minimum 200 mm (8 in)(7) 6.When ordered as floor plate (raised pattern), elongation requirements are not applicable. 7.Because plates wider than 610 mm (24 in) are tested in the transverse direction, the elongation requirement is reduced two percentage points for all grades up to grade 345 and three percentage points for all classes of Grades 415, 450, 486, and 550. Elongation(5)(6) Minimum % Minimum 50 mm (2 in)(7) Tensile Strength,(4) Max MPa Tensile Strength,(4) Max ksi 290A150629042415602024620 90 345A100434550450651821655 95 415A 3211/441560515751618690100 450A 3211/445065550801517725105 345W1004(8) 8.Refer to ASTM A 6/A 6M elongation requirement adjustments. 34550485701821655 95 345F 50234550415602023620 90 415F 4011/241560485701720655 95 485F 25148570550801417725105 550F 203/455080620901215795115 NOTES SAE J1442 Revised NOV93 -5- TABLE 1BMECHANICAL PROPERTIES(1) - STRUCTURAL SHAPES 1.Mechanical testing (location, number of tests, preparation, and method) is to be in accordance with the latest revision of ASTM A 6/ A 6M. Grade Nominal Maximum Size ASTM Group(2) 2.Refer to ASTM A 6/A 6M Table A. Yield(3)(4) Point Minimum MPa 3.May be reported as Yield Strength as measured by the 0.2% offset or or 0.5% extension under load method. 4.Only one set of units apply to yield and tensile and the reported value should be based on the units of the purchase order. In addi- tion, only one set of elongation values (2 in or 8 in) need to be met and reported. Yield(3)(4) Point Minimum ksi Tensile(4) Strength Minimum MPa Tensile(4) Strength Minimum ksi Elongation(4)(5)(6) % Minimum 200 mm (8 in) 5.For wide flange shapes over 634 kg/m (426 lb/ft), percent elongation in 50 mm (2 in) of 19 minimum applies. 6.For wide flange shapes over 634 kg/m (426 lb/ft), percent elongatation in 50 mm (2 in) of 18 minimum applies. Elongation(4)(5)(6) % Minimum 50 mm (2 in) 290AAll29042415602024 345AAll34550450651821 345WAll34550485701821 415A341560515751618 450A345065550801517 NOTES TABLE 2CHEMICAL COMPOSITION, HEAT ANALYSIS, MAX, % BY WEIGHT Grade Product P-Plate B-Bar S-ShapeCMnSiPSOther 290AP B, & S0.211.500.400.0400.050 (1) 1.Choice and use of alloying elements, combined with carbon, manganese, phosphorus, and sulfur within the limits of Table 2 to give the mechanical properties prescribed in Table 1A and 1B, shall be made by the manufacturer and included and reported in the heat analysis to identify the type of steel applied. Elements commonly added include: chromium, copper, molybdenum, nickel, columbium (niobium), vanadium, titanium, and zirconium. 345AP, B, & S0.231.500.400.0400.50 415AP, B, & S0.261.500.400.0400.050 450AP, B, & S0.261.650.400.0400.050 345WP, B, & S0.201.350.900.0400.050 345FP0.181.650.600.0250.035 415FP0.181.650.600.0250.035 485FP0.181.650.600.0250.035 550FP0.181.650.600.0250.035 SAE J1442 Revised NOV93 -6- 8.Notes 8.1Marginal IndiciaThe change bar (I) located in the left margin is for the convenience of the user in locating asreas where technical revisions have been mae to the previous issue of the report. An (R) symbol to the left of the document title indicates a complete revision of the report. PREPARED BY THE SAE IRON AND STEEL TECHNICAL COMMITTEE DIVISION 1 CARBON AND ALLOY STEELS TABLE 3SUGGESTED MINIMUM INSIDE RADII FOR 9