GOST 21073.1-75 PDF

Full title and description

GOST 21073.1-75 — "Non‑ferrous metals. Determination of grain size by comparison with microstructure scale". The standard specifies the comparative (visual) method for assigning a grain‑size number to non‑ferrous metals by matching micrographs of the test material with reference microstructure scales.

Abstract

This part of the GOST 21073 series defines the method of determining grain size in non‑ferrous metals by comparison with standardized microstructure scales (reference micrographs). It gives requirements for sampling locations, recommended microscope magnification (reference 100×), permitted alternative magnifications and the acceptable measurement uncertainty (generally within one scale number). Amendment No.1 (1984) has been incorporated into the text.

General information

• Status: Listed as implemented in many standards catalogues; some registries show it as still in use while others indicate it has been superseded or its status updated in later catalogues — users should verify with the national standards body for current legal status in their jurisdiction.
• Publication date: Designation year 1975; introduced/published around 1 July 1976 (dates in sources report 30 June–1 July 1976).
• Publisher: Originally issued under the USSR State Standards system (Gosstandart); later catalogued by national/international standards distributors.
• ICS / categories: Metallurgy / Non‑ferrous metals (classification references in commercial catalogues: 77.120.01 — non‑ferrous metals).
• Edition / version: GOST 21073.1-75 (original designation); Amendment No.1 (1984) is integrated in available texts.
• Number of pages: Typically published as a short technical leaflet (commonly shown as 6 pages in public catalogues).

Scope

Applies to non‑ferrous metals and alloys. Establishes a metallographic comparative method where micrographs (or prepared specimens viewed under a microscope) are compared with reference microstructure scales to determine grain‑size numbers. The procedure covers selection of measurement sites on a specimen, choice of appropriate reference scale, and rules for using alternative microscope magnifications with recalculation to the reference scale. Intended for routine laboratory and production quality control of grain size in non‑ferrous materials.

Key topics and requirements

• Definition of reference microstructure scales and grain‑size numbering used for non‑ferrous metals.
• Guidance on specimen preparation and selection of measurement locations (multiple fields, minimum number of observations for non‑uniform grain structure).
• Recommended microscope magnification (100×) and rules for converting counts taken at other magnifications to the reference scale.
• Permitted measurement uncertainty: generally not to exceed one number on the microstructure scale.
• Integration of Amendment No.1 (1984) into the standard text where applicable.

Typical use and users

Used by metallurgical laboratories, quality control and inspection departments in non‑ferrous metal production and processing, materials testing laboratories, research institutions, and engineering organizations that require metallographic grain‑size assessment for product specification, failure analysis, or process control. Also referenced by standards bodies when specifying metallographic acceptance criteria for non‑ferrous alloys.

Related standards

Part of the GOST 21073 series on grain‑size determination (for example: GOST 21073.0‑75 — General requirements; GOST 21073.2‑75, GOST 21073.3‑75, GOST 21073.4‑75 covering alternative metallographic methods). It is also used alongside other testing standards for non‑ferrous metals (hardness, microstructure preparation and imaging) and may be cross‑referenced by later national or interstate metallurgy standards.

Keywords

GOST 21073.1-75; non‑ferrous metals; grain size; microstructure scale; metallography; comparative method; microscope magnification; amendment 1984.

FAQ

Q: What is this standard?

A: GOST 21073.1‑75 is a national (USSR-origin) standard that defines the visual/comparative metallographic method for determining grain size in non‑ferrous metals by comparing test microstructures with standardized reference microstructure scales.

Q: What does it cover?

A: It covers specimen selection and observation rules, the use of reference microstructure scales, the recommended microscope magnification (reference 100×) and the procedure to convert results obtained at other magnifications, plus acceptable measurement uncertainty and notes from Amendment No.1 (1984).

Q: Who typically uses it?

A: Metallurgical testing and quality‑control laboratories, material engineers, foundries and producers of non‑ferrous alloys, and standards practitioners who need a standardized metallographic comparative procedure for grain‑size assessment.

Q: Is it current or superseded?

A: Public catalogues contain mixed signals — many commercial and archival catalogues list GOST 21073.1‑75 (with Amendment No.1 integrated) as implemented/available, while some registry entries indicate it may have been updated or its status revised in later compilations. For regulatory or procurement use you should confirm the current legal status with your national standards organization or the official standards registry.

Q: Is it part of a series?

A: Yes — it is one part of the GOST 21073 series addressing grain‑size determination in non‑ferrous metals; related parts include GOST 21073.0‑75 (general requirements), and the other method parts (.2,.3,.4) that cover alternative measurement techniques.

Q: What are the key keywords?

A: Non‑ferrous metals, grain size, microstructure scale, metallography, comparative method, GOST 21073.1‑75, amendment 1984.