BS EN 2951:2019 pdf download

BS EN 2951:2019 pdf download

BS EN 2951:2019 pdf download.Aerospace series – Metallic materials – Micrographic determination of content of non-metallic incl lusions
1 Scope
This document specifies the general requirements for the micrographic determination of content of non-metallic inclusions of metallic materials for aerospace applications.
It also gives tables of standard acceptance criteria for particular steel types.
It shall be applied when referred to in the EN technical specification or material standard unless otherwise specified on the drawing, order or inspection schedule.
This document is mainly applicable to steel but may be used on other metallic materials.
This document is not normally applicable to austenitic corrosion resisting steel, other than precipitation hardening, or to free-machining steel unless invoked in the material standards.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
EN 4258, Aerospace series 一Metallic materials 一General organization of standardization一Links between types of EN standards and their use
EN 4259, Aerospace series一Metallic materials一Definition of general terms 1)
ASTM E45, Standard Test Methods for Determining the Inclusion Content of Steel 2)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 4259 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
● IEC Electropedia: available at
●ISO Online browsing platform: available at http:/ /
4 Health and safety
Resources, test pieces, test samples, test materials, test equipments and test procedures shall comply with the current health and safety regulations/laws of the countries where the test is to be carried out. Where materials and/or reagents which may be hazardous to health are specified, appropriate precautions in conformity with local regulations and/or laws shall be taken.
5 Test method
Microscopical method A or method D of ASTM E45 is used.
The method used depends on the melting route and/or the requirement of the material standard and shall be in accordance with Table 1.
Method A: Counting shall be carried out on the worst field according to Method A of ASTM E45 standard over a surface of 160 mm2.
Method D: Counting shall be carried out according to Method D of ASTM E45 standard over a surface of 160 mm2 (i.e. 320 fields).
Other counting method shall be used prior agreement, in that case maximum series (thin and thick) allowed on 20 mm2 (40 fields).