ISO 12718:2019 pdf download

ISO 12718:2019 pdf download.Non-destructive testing — Eddy current testing — Vocabulary
1 Scope
This document defines terms used in eddy current testing.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www. electropedia.org/
3.1 General terms specifically associated with the eddy current test method
3.1.1 background noise noise (3.1.26) originating from geometric and metallurgical variations in the product to be tested Note 1 to entry: These effects may also be the subject of the measurement.
3.1.2 balance compensation of the signal, corresponding to the operating point (3.3.20). to achieve a pre- determined value Note 1 to entry: The predetermined value can be, for example, zero.
3.1.3 bandwidth range of frequencies in which a signal is transmitted or amplified in a linear way Note 1 to entry: Bandwidth is defined by the lower and upper cutoff frequencies which conventionally correspond to an attenuation of 3 dB. Note 2 to entry: Bandwidth can be defined for any or all elements of the system, such as a filter (.3.4.14). a cable or an amplifier.
3.1.5 characteristic frequency / conventional quantity used as a frequency unit Note 1 to entry: Characteristic frequency is derived from the mathematical model using Bessel functions to describe the eddy current distribution (3.1.101 in a cylindrical bar. The value is dependent on the characteristics of the product which influence this distribution, e.g. electrical conductivity, magnetic permeability and diameter. Note 2 to entry: Characteristic frequency,/ is given by:
3.1.6 characteristic frequency ratio dimensionless ratio of the ex- citation frequency (3.1.18) to the characteristic frequency (3.1.5) which enables the behaviour of electromagnetic quantities involved in the test to be gene- ralized Note 1 to entry: See law of similarity (iL24).’
3.1.7 coupling factor ratio of the excitation (3.1.19] flux through the product to be tested to the total excitation flux, which measures the elec- tromagnetic coupling (3.1.15) between the probe (3.3.40) and the product to be tested
3.1.8 demodulated signal eddy current signal after demo- dulation
3.1.9 differentiated signal output signal of a differential filter (3.4.8)
3.1.10 eddy current distribution vector field of eddy current density 3.1.11 eddy current testing non-destructive testing method using the electromagnetic effects of induced currents to evaluate the product to be tested