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ASTM A781-2020 pdf free download

ASTM A781-2020 pdf free download.Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
4. Materials and Manufacture
4.1 Melting Process—The steel shall be made by open- hearth or electric furnace process with or without separate refining, such as argon-oxygen-decarburization (AOD), unless otherwise specified in the individual specification. 4.2 Heat Treatment: 4.2.1 Castings shall be heat treated in the working zone of a furnace that has been surveyed in accordance with Test Method A991/A991M or AMS 2750. 4.2.2 When using furnaces surveyed in accordance with Test Method A991/A991M, the following requirements apply for heat treatments above 2000 °F [1100 °C]. When castings are heat treated at temperatures above 2000 °F [1100 °C], then the working zone shall have been established by a survey performed at not more than 25 °F [15 °C] below nor more than 200 °F [110 °C] above the minimum heat treatment tempera- ture specified for the grade. If a minimum heat treatment temperature is not specified for the grade, then the survey temperature shall be not more than 50 °F [30 °C] below nor more than 175 °F [100 °C] above the furnace set point used. 4.2.3 When using furnaces surveyed in accordance with AMS 2750, there are no additional requirements beyond those stated in AMS 2750. 4.2.4 The maximum variation in measured temperature, as determined by the difference between the highest temperature and the lowest temperature, shall be as agreed between the purchaser and producer, except that during production heat treatment no portion of the furnace shall be below the minimum specified temperature nor above the maximum specified temperature for the grade being processed.
6. Mechanical Test Requirements
N OTE 1—The tension testing requirements of this specification are intended only to characterize the tensile properties of the heat for determination of conformance to the requirements of the applicable product specification. Such testing procedures are not intended to define the upper or lower limits of tensile properties at all possible test locations within a heat. It is well known and documented that tensile properties will vary within a heat or individual casting as a function of chemical composition, processing, testing procedure, and other factors. 4 It is, therefore, incumbent on designers and engineers to use sound engineering judgement when using tension test results. 6.1 The individual product specifications vary as to whether mechanical tests are required; for this reason, and to determine specific test requirements, the individual product specification should be reviewed. 6.2 Unless otherwise specified by the purchaser, when mechanical properties are required by the product specification, test coupons may be cast integrally with the castings, or as separate blocks, in accordance with Specifica- tion A1067/A1067M, Fig. 1, Fig. 2, or Fig. 4, except when Supplementary Requirement S15 is specified. The test coupon in Specification A1067/A1067M, Fig. 4 may be employed only for austenitic stainless steel and nickel-base alloy castings with cross sections less than 2 1 ⁄ 2 in. [65 mm]. 6.3 Test specimens may be cut from heat-treated castings, at the producer’s or the purchaser’s option, instead of from separately cast test coupons. 6.4 Choice of testing track from the options listed in Test Methods A1058 when material is ordered to an M-suffix (SI units) product standard should be identified by the purchaser in the ordering information. If the choice of test track is not specified in the order, then the default ASTM track shall be used as noted in Test Methods A1058. 6.5 The coupon from which the test specimen is taken shall be heat treated in production furnaces to the same procedure as the castings it represents. 6.6 The specimens may be cast to shape or machined from coupons to dimensions in accordance with Test Methods and Definitions A370. 6.7 To determine conformance with the tension test requirements, an observed value or calculated value shall be rounded off in accordance with Practice .

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