IEC 60401-1:2020 pdf free download – Terms and nomenclature for cores made of magnetically soft ferrites
1Scope
This part of lEC 60401 provides a nomenclature of the most frequent surface, bulk and shapeirregularities relevant to cores made of soft ferrites (magnetic oxides). Most irregularities aregraphically exemplified as visual aids.A general recommendation is also given in Annex A fora consistent scheme for specifying the exact location of the irregularity,combining a generalname for the location with more detailed qualifiers of the specified location.This documentcan also be useful as a terminology reference when preparing technical documentation,irregularity inspection specifications, etc.
This document also presents a method for defining the designation nomenclature for themajor physical attributes of soft ferrite core shapes. The purpose of this document is tofacilitate uniform usage of dimensional characters by manufacturers，specifiers，and userswhen describing core dimensions on drawings，in tables，and on catalogue specificationsheets.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document,the terms and definitions given in 4.2，4.3，4.5 andAnnex A apply.
ISO and lEC maintain terminological databases for use in standardization at the followingaddresses:
·lEC Electropedia: available at http://www.electropedia.orgl
. ISO Online browsing platform: available at http://www.iso.org/obp4Physical irregularities
4.1General overview
Physical irregularities mean here the surface irregularities, bulk irregularities and shapeirregularities. The irregularity here stands for inconsistency of the state or quality of the part’ssurface, bulk or shape with its intended regularity.These irregularities are considered here inthe macroscopic scale， i.e. within the range of linear dimensions of irregularities from onemicrometre to tens of millimetres.
There is a great variety of surface, bulk and shape irregularities degrading the quality of partsmade of ferrites. Different types of these irregularities can often occur together and overlapone another.
4.3.4.1crack
surface irregularity which has a width much smaller than its length and penetrates into thecore
4.3.4.2 single-surface narrow crack
crack located on a single surface, not going beyond its edges,and with a width not exceedinga specified limit (e.g. 0,1 mm) anywhere along the crack path on the surface SEE. Figure 10.
4.4 lnterior irregularities
Since inclusions,cracks or lamination that is confined to the inside of a part cannot bedetected by direct inspection except with destructive or expensive procedures, control of bulkirregularities is maintained through break strength testing.Small sample sizes from productionbatches are destructively broken with M testing， W testing,or tensile pull testing. The yieldstrength is recorded and compared with specification limits or control limits. Further,internalirregularities that cause electrical performance to be impaired are detected by means oftesting against the electrical specifications.