# ISO 643:2019 — Withdrawn and superseded ISO standards

For ISO 643:2019, item title is Steels — Micrographic determination of the apparent grain size; status code is 9599; successor is ISO 643:2024; withdrawn / published date is 2019-12-12, recorded from its source on 2026-08-05.

- **Identifier:** ISO 643:2019 _(verified: appears in the quote below)_
- **Item title:** Steels — Micrographic determination of the apparent grain size _(verified: appears in the quote below)_
- **Status code:** 9599 _(verified: appears in the quote below)_
- **Successor:** ISO 643:2024
- **Withdrawn / published date:** 2019-12-12 _(verified: appears in the quote below)_

## What the source says

> 72193,IS,,ISO 643:2019,Steels — Micrographic determination of the apparent grain size,Aciers — Détermination micrographique de la grosseur de grain apparente,2019-12-12,4,['77.040.99'],ISO/TC 17/SC 7,9599,[61697],[82221],"['en','fr']",21,"<p>This document specifies a micrographic method of determining apparent ferritic or austenitic grain size in steels. It describes the methods of revealing grain boundaries and of estimating the mean grain size of specimens with unimodal size distribution. Although grains are three-dimensional in shape, the metallographic sectioning plane can cut through a grain at any point from a grain corner, to the maximum diameter of the grain, thus producing a range o

## Source

- https://isopublicstorageprod.blob.core.windows.net/opendata/_latest/iso_deliverables_metadata/csv/iso_deliverables_metadata.csv

Last verified: 2026-08-05. Review by: 2027-02-01.
Part of [Withdrawn and superseded ISO standards](https://referencesource.org/iso-standard-supersessions/).