List-Magnetik GmbH EN FERRITE-CHECK 110 2022-11.doc 2
1. INTRODUCTION
With FERRITE-CHECK 110 you can easily and quickly measure the errite content in
steels according to ISO 8249.
ISO 8249 particularly ocuses on austenitic steel and duplex steel ( erritic / austenit-
ic) to be evaluated or welding operations: i the errite content is too low, the weld
metal becomes susceptible to cracking; i the errite content is too high, toughness
and corrosion resistance are reduced. For duplex steels, a lack o errite at the weld
causes a reduction in strength.
The determined errite number is a description o the errite content in a weld metal,
which is determined in a standardized procedure. Instead o the errite number (FN),
the errite content (Fe%) can also be determined. The conversion is about 70% o
the FN value. The errite content determined as Fe% does not necessarily corre-
spond to the actual or absolute errite content. There ore, the errite number is more
commonly used.
Uneven or round sur aces (as on rods), as well as contamination o the sur ace, can
lead to incorrect or inaccurate measured values
FERRITE-CHECK 110 is pre-calibrated, but is supplied with three calibration
standards or easy recalibration. The instrument is calibrated be ore delivery using
calibration standards provided by the National Institute o Standards and Technology
(NIST).
The "FN140" standard placed on the le t in the case has a bright steel sur ace and is
to be used or zero calibration (base calibration) during two-point calibration.
In the center and right o the case are two standards covered with copper oil. They
represent di erent errite numbers (approx. 6, approx. 17). The exact value is
written on the respective standard.
The standard with the lower FN number is also used or the two-point calibration, the
second step, called FN calibration.
Alternatively, you can also calibrate with the third standard, especially i you
regularly have higher errite values on your workpieces. This increases the accuracy
o these measurements.
