(812) 309-78-59
(495) 223-46-76
ASTM E930-99(2015)
Standard Test Methods for Estimating the Largest Grain Observed in a Metallographic Section (ALA Grain Size)
6 стр.
Заменен
Печатное изданиеЭлектронный (pdf)
96.72 $ (включая НДС 20%)
Разработчик:
Зарубежные/ASTM
ICS:
19.120 Particle. Including test sieves and porosimetry / Ситовый анализ. Просеивание. Включая контрольные сита и измерение пористости
Сборник (ASTM):
03.01 Metals -- Mechanical Testing; Elevated and Low-Temperature Tests; Metallography / Металлы - Механические испытания, Испытания при высоких и низких температурах, Металлография
Тематика:
Physical & Mechanical Testing
Описание
Значение и использование

4.1 The presence of large grains has been correlated with anomalous mechanical behavior in, for example, crack initiation, crack propagation, and fatigue. Thus there is engineering justification for reporting the ALA grain size.

4.2 These methods shall only be used with the presence of outlier coarse grains, 3 or more ASTM grain size numbers larger than the rest of the microstructure and comprising 5 % or less of the specimen area. A typical example is shown in Annex A1 as Fig. A1.1.

4.3 These methods shall not be used for the determination of average grain size, which is treated in Test Methods E112. Examples of microstructures that do not qualify for ALA treatment are shown in Annex A1 as Fig. A1.2, Fig. A1.3, and Fig. A1.4.

4.4 These methods may be applied in the characterization of duplex grain sizes, as instructed in the procedures for Test Methods E1181.

Область применения

1.1 These test methods describe simple manual procedures for measuring the size of the largest grain cross-section observed on a metallographically prepared plane section.

1.2 These test methods shall only be valid for microstructures containing outlier coarse grains, where their population is too sparse for grain size determination by Test Methods E112.

1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Ключевые слова:
ALA grain; caliper diameter; comparison procedure; ellipse measurement; grain size; largest grain; measuring procedure; metallography; microstructure; outlier grain; point-count procedure;