定价： 0元 / 折扣价： 0 元 加购物车

定价： 605元 / 折扣价： 515 元

4.1 For ferromagnetic materials, magnetic particle examination is widely specified for the detection of surface and near surface discontinuities such as cracks, laps, seams, and linearly oriented nonmetallic inclusions. Such examinations are included as mandatory requirements in some forging standards such as Specification A508/A508M.4.2 Use of direct current or rectified alternating (full or half wave) current as the power source for magnetic particle examination allows detection of subsurface discontinuities.AbstractThis test method covers the procedures for the standard practice of performing magnetic particle examination on steel forgings. The inspection medium shall consist of finely divided ferromagnetic particles, whose size, shape and magnetic properties, both individually and collectively, shall be taken into account. Forgings may be magnetized in the longitudinal or circular direction by employing the surge or continuous current flow methods. Magnetization may be applied by passing current through the piece or by inducing a magnetic field by means of a central conductor, such as a prod or yoke, or by coils. While the material is properly magnetized, the magnetic particles may be applied by either the dry method, wet method, or fluorescent method. The parts shall also be sufficiently demagnetized after inspection so that residual or leakage fields will not interfere with future operations to which the steel forgings shall be used for. Indications to be evaluated are grouped into three broad classes, namely: surface defects, which include laminar defects, forging laps and folds, flakes (thermal ruptures caused by entrapped hydrogen), heat-treating cracks, shrinkage cracks, grinding cracks, and etching or plating cracks; subsurface defects, which include stringers of nonmetallic inclusions, large nonmetallics, cracks in underbeads of welds, and forging bursts; and nonrelevant or false indications, which include magnetic writing, changes in section, edge of weld, and flow lines.1.1 This practice2 covers a procedure for magnetic particle examination of steel forgings. The procedure will produce consistent results upon which acceptance standards can be based. This practice does not contain acceptance standards or recommended quality levels.1.2 Only direct current or rectified alternating (full or half wave) current shall be used as the electric power source for any of the magnetizing methods. Alternating current is not permitted because its capability to detect subsurface discontinuities is very limited and therefore unsuitable.1.2.1 Portable battery powered electromagnetic yokes are outside the scope of this practice.NOTE 1: Guide E709 may be utilized for magnetic particle examination in the field for machinery components originally manufactured from steel forgings.1.3 The minimum requirements for magnetic particle examination shall conform to practice standards of Practice E1444/E1444M. If the requirements of this practice are in conflict with the requirements of Practice E1444/E1444M, the requirements of this practice shall prevail.1.4 This practice and the applicable material specifications are expressed in both inch-pound units and SI units. However, unless the order specifies the applicable “M” specification designation [SI units], the material shall be furnished to inch-pound units.1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

1.1 This specification covers wrought, microalloyed carbon steel forgings for industrial use. Microalloyed steels develop their properties by the addition of small amounts of microalloying elements such as vanadium, columbium, titanium, or molybdenum. The properties may be influenced also by control of the hot working process and temperature and by control of the subsequent cooling rate.1.2 The forgings shall be furnished to chemical composition and mechanical property requirements as specified herein. Chemical composition is based on standard carbon steel grades modified to include microalloying elements. Strength level is specified based on desired mechanical properties in the forgings. Depending on the forging process, different strength classes may be attainable from a single chemical composition. Conversely, mechanical properties of a given strength class may be achieved using different chemical compositions. The manufacturer should be consulted if development of chemical composition is necessary.1.3 For the purpose of this specification, forgings with maximum section thickness of 4 in. [100 mm] are to be considered.1.4 Supplementary Requirements S1 to S8 are provided for use when additional controls or requirements are desired. These shall apply only when specified on the purchase order.1.5 The values stated in either inch-pound units or SI (metric) units are to be regarded separately as standard. Within the text and tables, SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.6 Unless the order specifies the applicable “M” specification designation, the material shall be furnished to the inch-pound units.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers quenched and tempered carbon and alloy steel forgings for magnetic retaining rings for turbine generators. Specimens shall be manufactured by melting process and vacuum degassing. Forgings shall also undergo preliminary machining prior to heat treatment (quenching and tempering) for mechanical properties testing. Steel materials shall conform to tensile and notch toughness requirements, which include tensile strength, yield strength, elongation, reduction of area, and Charpy V-notch impact strength. Heat and product analyses shall be performed as well wherein specimens shall conform to chemical requirements of carbon, manganese, phosphorus, sulfur, nickel, chromium, molybdenum, and vanadium. Nondestructive tests such as magnetic particle test and ultrasonic inspection may also be performed.1.1 This specification covers quenched and tempered carbon and alloy steel forgings for magnetic retaining rings for turbine generators.1.2 Supplementary requirements of an optional nature are provided. These shall apply only when specified by the purchaser.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

This specification deals with normalized and tempered, and quenched and tempered, carbon and alloy steel forged or rolled rings for reduction gears. The grades and classes of steels covered here are: Grade 1, Classes A and B, and Grade 2, Classes C and D, which are carbon steels; and Grade 3, Classes E and F, Grade 4, Classes G, H, I, J, K and L, Grade 5, Classes M and P, and Grade 6, Class T, which are alloy steels. Materials shall be manufactured by melting and forging processes and optional machining, and shall be allowed to cool prior to reheating. Heat treatment shall consist of normalizing and tempering for Grade 1, Classes A and B, and quenching and tempering for all other grades and classes. Heat and product analyses shall be performed wherein specimens shall conform to required chemical composition of carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, vanadium, copper, and aluminum. Steels shall also undergo tension, impact, and Brinell hardness tests, and shall conform to the following mechanical requirements: tensile strength, yield strength, elongation, reduction of area, Brinell hardness, and Charpy V-notch.1.1 This specification covers normalized and tempered, and quenched and tempered, carbon and alloy steel forged or rolled rings for reduction gears.1.2 Several grades and classes of steel are covered as follows:1.2.1 Grade 1, Classes A and B, and Grade 2, Classes C and D, are carbon steel.1.2.2 Grade 3, Classes E and F, Grade 4, Classes G, H, I, J, K and L, Grade 5, Classes M and P, and Grade 6, Class T, are alloy steel.1.2.3 All grades and classes are considered weldable under proper conditions. Welding techniques are of fundamental importance and it is pre-supposed that welding procedure and inspection will be in accordance with proper methods for the class of material used.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers vacuum treated and differentially heat treated alloy steel forgings for turbine rotors. Materials shall be manufactured by melting process, heat treatment (consisting of normalizing and tempering to achieve creep resistance in the high pressure portion, and quenching and tempering to achieve high toughness in the low pressure portion), rough machining, and boring. Heat and product analyses shall be performed to evaluate conformance of the steel to required chemical compositions. Tension and impact tests shall also be executed to make sure that forgings adhere to tensile and notch toughness requirements, including tensile strength, yield strength, elongation, and reduction of area. Final products shall be free of cracks, seams, laps, shrinkage, and other injurious imperfections. To evaluate such imperfections, nondestructive tests, such as ultrasonic and internal inspection procedures, may be conducted at the preference of the purchaser. Forgings that do not meet the requirements specified, may be retreated one or more times, but not more than three additional times.1.1 This specification covers vacuum treated, alloy steel forgings, differentially heat treated for turbine rotors.1.2 Differential heat treatment of a rotor forging involves subjecting two portions of the forging concurrently to two different austenitizing temperatures followed by two different cooling rates for normalizing and quenching, and then tempering, to achieve creep resistance in the high pressure (HP) portion and high toughness in the low pressure (LP) portion.21.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

定价： 0元 / 折扣价： 0 元

This specification deals with ferritic alloy steel forgings for high-pressure and high-temperature parts, such as boilers, pressure vessels, and associated equipment. The steel grades covered here include the following: Grade F1; Grade F11, Classes 1, 2, and 3; Grade F12; Grade F5; Grade F5A; Grade F9; Grade F6; Grades F21 and F22, Classes 1 and 3; Grade F91, Grade F3V; and Grade F22V. Other steel grades may also be treated under this specification. Alloy steels shall be melted, forged, and rough machined at stipulated conditions. Except as permitted for Grade F22V, steel forgings shall be annealed or normalized and tempered, but may alternatively be liquid quenched and tempered as well. Impact and Charpy V-notch tests shall be performed wherein specimens shall conform to specified mechanical requirements such as notch toughness, tensile strength, yield strength, elongation, and reduction of area. Materials shall also undergo heat and product analyses and conform to specified chemical requirements.1.1 This specification2 covers ferritic steel forgings for boilers, pressure vessels, high-temperature parts, and associated equipment.1.2 Forgings made of steel grades listed in Specification A335/A335M may also be ordered under this specification. The chemical, tensile, heat treatment, and marking requirements of Specification A335/A335M shall apply, except the forging shall conform to the chemical requirements of Tables 1 and 2 of Specification A335/A335M only with respect to heat analysis. On product analysis they may deviate from these limits to the extent permitted in Table 1 of this specification.1.3 Supplementary Requirements S1 to S10 are provided for use when additional testing or inspection is desired. These shall apply only when specified individually by the purchaser in the order.1.4 Unless the order specifies the applicable “M” specification designation, the material shall be furnished to the inch-pound units.1.5 Specification A336/A336M formerly included austenitic steel forgings, which are now found in Specification A965/A965M.1.6 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

This specification establishes the requirements for copper-beryllium alloy forgings and extrusions. The following alloys are specified: UNS No. C17500 and C17510. The material of manufacture should be a cast billet conforming to the chemical composition requirements for the alloy specified. The product shall be manufactured by hot working or extrusion, solution heat-treating, precipitation hardening, and straightening. The material shall conform to the chemical composition for the alloy specified. The material shall conform to the electrical conductivity requirements specified. Hardness test and tensile test shall be made to conform to the requirements specified.1.1 This specification establishes the requirements for copper-beryllium alloy forgings and extrusions. The following alloys are specified:Copper AlloyUNS No. Nominal Composition, %Beryllium Cobalt NickelC17500 0.50 2.6 ...C17510 0.40 ... 1.8C17540 0.50 1.5 1.51.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 The following safety hazard caveat pertains to Sections 10 and 11 of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers the chemical composition and mechanical requirements for 35cobalt-35nickel-20chromium-10molybdenum alloy (UNS R30035) forgings for use in surgical implants. The material covered here shall be in the form of bars, plates, sheets, or wires manufactured in the solution-annealed condition with a finish suitable for forging by hammering, pressing, rolling, extruding, or upsetting.1.1 This specification covers the chemical, mechanical, and metallurgical requirements for 35cobalt-35nickel-20chromium-10molybdenum alloy (UNS R30035) in the form of forgings, used for the manufacture of surgical implants.1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 618元 / 折扣价： 526 元 加购物车

定价： 345元 / 折扣价： 294 元 加购物车

This specification deals with the standard requirements for untreated and heat-treated carbon and alloy steel forgings for general industrial use. This specification covers six classes of carbon steels (Class A to F) and seven classes of alloy steels (Class G, H, and J to N). Materials shall be forged by hot mechanical work. Except for Class A, all forgings shall be heat treated, depending on class, by the following techniques: annealed, or normalized, or normalized and tempered (Classes B, C, D, and G); normalized and tempered, or double-normalized and tempered (Class E); quenched and tempered, or normalized, quenched, and tempered (Classes F); normalized and tempered (Class H); normalized and tempered, or normalized, quenched, and tempered (Class J); and normalized, quenched, and tempered (Classes K, L, M, and N). Steel specimens shall undergo heat and product analyses, and shall conform to required chemical compositions for manganese, phosphorus, and sulfur. Steel forgings shall also be tested on their conformance to the following tensile requirements: tensile strength, yield point, yield strength, elongation, reduction of area, and Brinell hardness.1.1 This specification covers untreated and heat-treated carbon and alloy steel forgings for general industrial use. Other ASTM specifications for forgings are available for specific applications such as pressure vessels, railroad use, turbine generators, gearing, and others involving special temperature requirements.1.2 Hot-rolled or cold finished bars are not within the scope of this specification.1.3 Six classes of carbon steel and seven classes of alloy steel forgings are listed (see Section 7), which indicate their required heat treatments, as well as mechanical properties.1.4 Provision, with the suffix H for certification and marking, for the supply of forgings after hardness testing only.1.5 Supplementary requirements, including those in Specification A788/A788M, of an optional nature are provided. These shall apply only when specified by the purchaser.1.6 Appendix X1 lists the current classes corresponding to the various classes of Specifications A235, A237, and A243, which have been superseded by this specification.1.7 The values stated in either SI units or inch-pound units are to be regarded separately as standard; within the text and tables, the SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.8 Unless the order specifies the applicable “M” specification, the forgings shall be furnished to the inch-pound units.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

This specification covers normalized and tempered carbon steel, and liquid quenched and tempered alloy steel forgings for pinions, gears, and shafts for reduction gears. Prior to heat treatment for mechanical properties testing , steel materials may undergo machining and boring, after which specimens shall be stress relieved. Tensile, impact and Brinell hardness tests shall be performed wherein forgings shall conform to the following mechanical properties: tensile strength, yield strength, elongation, reduction of area, Charpy V-notch, and Brinell hardness. Specimens shall also conform to chemical requirements for carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, vanadium, copper, and aluminum.1.1 This specification covers normalized and tempered carbon steel and quenched and tempered alloy steel forgings for pinions, gears, and shafts.1.2 Several grades of steel are covered as follows:1.2.1 Grade 1, Class A,  is normalized and tempered carbon steel.1.2.2 Grade 2, Class B, Grade 3, Class C, Grade 3A, Class D, Grades 4 to 7, Classes E, F, G, and H, Grade 8, Class I, and Grade 9, Class J,  are liquid quenched and tempered alloy steel.1.3 All grades and classes are considered weldable under proper conditions. Welding technique is of fundamental importance and it is presupposed that welding procedure and inspection shall be in accordance with approved methods for the class of material used.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

This specification establishes the requirements for copper and copper die forgings produced by hot pressing method. The forgings included here are designated with the following Copper or Copper Alloy UNS Nos.: C11000 (copper), C14500 (copper-tellurium alloy), C14700 (copper-sulfur alloy), C36500 (leaded Muntz metal), C37000 (free-cutting Muntz metal), C37700 (forging brass), C46400 (naval brass), C48200 (medium leaded naval brass), C48500 (leaded naval brass), C61900 (aluminum bronze), C62300 (9% aluminum bronze), C63000 and C63200 (aluminum-nickel bronze), C64200 (aluminum-silicon bronze), C64210 (6.7% aluminum-silicon bronze), C65500 (high-silicon bronze), C67500 (manganese bronze), C67600, C69300 (copper-zinc-silicon alloy), C70620 (90% copper-10% nickel alloy), C71520 (70% copper-30% nickel alloy), and C77400 (45% nickel-10% silver alloy). The materials for manufacture shall be rods, billets, or blanks of such purity and soundness as to be suitable for processing by hot pressing. Products shall be tested to examine their conformance to mechanical (tensile and yield strengths, and elongation), dimensional, and chemical composition requirements.1.1 This specification establishes the requirements for copper and copper alloy die forgings produced by the hot pressing method. The following copper and copper alloys are included:Copper or Copper Alloy UNS No. NameC11000     copperC14500     copper-telluriumC14700     copper-sulfurC27450     plumbing brassC27451     plumbing brassC27453     copper zinc alloyC28500     copper-zinc brassC35330     leaded brassC36300     copper-zinc-leadC36500     leaded Muntz metalC37000     free-cutting Muntz metalC37700     forging brassC46400     naval brassC46500     naval brass, arsenicalC46750     tin brassC48200     medium leaded naval brassC48500     leaded naval brassC48600     naval brassC48640     DZR brassC48645     DZR tin brassC49250     copper-zinc-bismuth alloyC49255     copper-zinc-bismuth-nickel alloyC49260     copper-zinc-bismuth alloyC49265     copper-zinc-tin-bismuth, low leadedC49300     copper-zinc-tin-bismuth alloyC49340     copper-zinc-tin-bismuth alloyC49345     copper-zinc-tin-bismuth, low leadedC49350     copper-zinc-tin-bismuth alloyC49355     bismuth brassC61900     aluminum bronzeC62300     aluminum bronze, 9 %C63000     aluminum-nickel bronzeC63200     aluminum-nickel bronzeC64200     aluminum-silicon bronzeC64210     aluminum-silicon bronze, 6.7 %C65500     high-silicon bronze (A)C65680     high-silicon bronzeC67500     manganese bronze (A)C67600     . . .C69300     copper-zinc-siliconC69410     copper-zinc-siliconCopper or Copper Alloy UNS No. NameC69850     copper-zinc-siliconC70620     copper-nickel 90-10C71520     copper-nickel 70-30C77400     nickel silver, 45-10C87700     silicon bronzeC87710     silicon bronze   Copper Alloy EN 1412 Nos. NameCW612N     forging brassCW617N     forging brass1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other and values from the two systems shall not be combined.NOTE 1: Nominal composition and relative forgeability ratings are given in Appendix X1. Copper-nickel alloys C70620 and C71520 are intended for welded applications with seawater exposure.NOTE 2: Guidelines for design and development of forgings are included in Appendix X2.NOTE 3: Wrought product intended for hot forging is described in Specification B124/B124M.1.3 The following safety caveat pertains only to Section 10 of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 646元 / 折扣价： 550 元 加购物车

4.1 Macroetching is used in the steel industry because it is a simple test that will provide information about the relative homogeneity of the sample. The method employs the action of an acid or other corrosive agent to develop the macrostructural characteristics of a suitably prepared specimen. The name implies that the etched surface is examined visually, or at low magnifications (usually <10×).4.2 Macroetching will show: (1) variations in structure such as grain size, dendrites, and columnar structure; (2) variations in chemical composition such as segregation, coring, and banding; and, (3) the presence of discontinuities such as laps, seams, cracks, porosity, bursts, pipe. and flakes.4.3 When, in accordance with the requirements of the inquiry, contract, order or specifications, forgings, billets, blooms, etc., are to be produced subject to macroetch testing and inspection, the manufacturer and the purchaser should be in agreement concerning the following: (1) the stage of manufacture at which the test shall be conducted; (2) the number and locations of the sections to be examined; (3) the necessary surface preparation prior to etching of the specimen; (4) the etching reagent, temperature, and time of etching; and, (5) the type, size, number, location, and orientation of conditions that are to be considered injurious.4.4 When not specified, the procedures of the test may be selected by the manufacturer to satisfy the requirements of the governing specification.4.5 When agreed upon by purchaser and producer, sulfur printing of as cast-sections, if continuously cast, is an acceptable alternative to macroetching. Sulfur printing shall be performed in accordance with Practice E1180. Examination and rating of specimens shall be in accordance with Sections 10 and 11 of this (E381) standard.4.6 Steel from ingots, in the wrought condition, shall be examined according to procedures described in Section 9. Continuously cast steel blooms and billets, in the as cast condition, shall be examined according to the procedures described in Sections 10 and 11. With reductions over a 3:1 area ratio, wrought product from continuously cast steel may be examined according to Section 9.4.7 The “R” series of photographs in Plate I shall not be used to rate Type A segregates, occasionally referred to as “carbon spots” and “sulfur segregation.” Type A segregates form in channels of the liquid-solid zone of large, solidifying ingots and appear as dark spots, including pitting due to removal of indigenous manganese sulfide microinclusions, on etched transverse sections of resultant forgings due to chemical and microinclusion content differences with the matrix. They appear as streaks in etched longitudinal sections and contain elevated levels of segregation-prone elements such as C, S, P, Si, Mn, Cr and manganese sulphide microinclusions. While Type A segregate patterns (including accompanying MnS pitting) have some similarities in appearance with the conditions in the Plate I “R” series photographs, they can be distinguished from the R series conditions because they are more symmetrically arrayed about the section center, and individual spots are typically more uniform in size at a given radius. The photographs in Annex I depict the presence of Type A segregates. The nature of questionable indications should be verified by microscopic examination or other means of inspection.1.1 Macroetching, which is the etching of specimens for macrostructural examination at low magnifications, is a frequently used technique for evaluating steel products such as bars, billets, blooms, and forgings.1.2 Included in this method is a procedure for rating steel specimens by a graded series of photographs showing the incidence of certain conditions. The method is limited in application to bars, billets, blooms, and forgings of carbon and low alloy steels.1.3 A number of different etching reagents may be used depending upon the type of examination to be made. Steels react differently to etching reagents because of variations in chemical composition, method of manufacture, heat treatment and many other variables. Establishment of general standards for acceptance or rejection for all conditions is impractical as some conditions must be considered relative to the part in which it occurs.1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See the specific precautionary statement in 5.3.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车