ISO 643:2019

Steels — Micrographic determination of the apparent grain size ISO 643:2019

General information

90.92 Standard to be revised   Nov 27, 2020

ISO

ISO/TC 17/SC 7 Methods of testing (other than mechanical tests and chemical analysis)

International Standard

77.040.99   Other methods of testing of metals

Scope

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 of apparent grain sizes on the two-dimensional plane, even in a sample with a perfectly consistent grain size.

Life cycle

PREVIOUSLY

WITHDRAWN
ISO 643:2012

NOW

PUBLISHED
ISO 643:2019
90.92 Standard to be revised
Nov 27, 2020

REVISED BY

IN_DEVELOPMENT
ISO/DIS 643