ASME SA370-2015 pdf download

ASME SA370-2015 pdf download.TEST METHODS AND DEFINITIONS FOR MECHANICAL TESTING OF STEEL PRODUCTS.
8.1.3 Cast Steels — Test coupons for castings from whichtension testspecimens arepreparedshall be in accor- dance with the requirements of Specifications A 703/A 703M or A 781/A 781M, as applicable. 8.2 Size and Tolerances — Test specimens shall be the full thickness or section of material as-rolled, or may be machined to the form and dimensions shown in Figs. 3–6, inclusive. The selection of size and type of specimen is prescribed by the applicable product specification. Full section specimens shall be tested in 8 in. (200 mm) gage length unless otherwise specified in the product specifi- cation. 8.3 ProcurementofTestSpecimens — Specimens shall be sheared, blanked, sawed, trepanned, or oxygen-cut from portions of the material. They are usually machined so as to have a reduced cross section at mid-length in order to obtain uniform distribution of the stress over the cross section and to localize the zone of fracture. When test coupons are sheared, blanked, sawed, or oxygen-cut, care shall be taken to remove by machining all distorted, cold- worked, orheat-affectedareas from the edges ofthe section used in evaluating the test. 8.4 Aging ofTestSpecimens — Unless otherwise speci- fied, it shall be permissible to age tension test specimens. The time-temperature cycle employed must be such that the effects of previous processing will not be materially changed. It may be accomplished by aging at room temper- ature 24 to 48 h, or in shorter time at moderately elevated temperatures by boiling in water, heating in oil or in an oven. 8.5 Measurement ofDimensions ofTest Specimens: 8.5.1 Standard Rectangular Tension Test Speci- mens — These forms of specimens are shown in Fig. 3. To determine the cross-sectional area, the center width dimension shall be measured to the nearest 0.005 in. (0.13 mm) for the 8 in. (200 mm) gage length specimen and 0.001 in. (0.025 mm) for the 2 in. (50 mm) gage length specimen in Fig. 3. The center thickness dimension shall be measured to the nearest 0.001 in. for both specimens. 8.5.2 Standard Round Tension Test Specimens — These forms of specimens are shown in Fig. 4 and Fig. 5. To determine the cross-sectional area, the diameter shall be measured at the center of the gage length to the nearest 0.001 in. (0.025 mm) (see Table 1). 8.6 General — Test specimens shall be either substan- tially full size or machined, as prescribed in the product specifications for the material being tested. 8.6.1 Improperly preparedtestspecimens oftencause unsatisfactory test results. It is important, therefore, that care be exercised in the preparation of specimens, particu- larly in the machining, to assure good workmanship. 8.6.2 It is desirable to have the cross-sectional area of the specimen smallest at the center of the gage length to ensure fracture within the gage length. This is provided for by the taper in the gage length permitted for each of the specimens described in the following sections. 8.6.3 Forbrittle materials itis desirable to have fillets of large radius at the ends of the gage length. 9. Plate-Type Specimen 9.1 The standard plate-type test specimen is shown in Fig. 3. This specimen is used for testing metallic materials in the form of plate, structural and bar-size shapes, and flat material having a nominal thickness of 3 ⁄ 16 in. (5 mm) or over. When product specifications so permit, other types of specimens may be used. NOTE 3 — When called for in the product specification, the 8 in. gage length specimen of Fig. 3 may be used for sheet and strip material. 10. Sheet-Type Specimen 10.1 The standard sheet-type test specimen is shown in Fig. 3. This specimen is used for testing metallic materi- als in the form of sheet, plate, flat wire, strip, band, and hoop ranging in nominal thickness from 0.005 to 3 ⁄ 4 in. (0.13 to 19 mm). When product specifications so permit, other types of specimens may be used, as provided in Section 9 (see Note 3). 11. Round Specimens 11.1 The standard 0.500 in. (12.5 mm) diameter round test specimen shown in Fig. 4 is used quite generally for testing metallic materials, both cast and wrought. 11.2 Fig. 4 also shows small size specimens propor- tional to the standard specimen. These may be used when it is necessary to test material from which the standard specimen orspecimens shown in Fig. 3 cannotbe prepared. Other sizes of small round specimens may be used. In any such small size specimen it is important that the gage length for measurement of elongation be four times the diameter of the specimen (see Note 4, Fig. 4). 11.3 The shape of the ends of the specimens outside of the gage length shall be suitable to the material and of a shape to fit the holders or grips of the testing machine so thattheloads areappliedaxially. Fig. 5 shows specimens with various types of ends that have given satisfactory results.