| Summary: | Due to the existing relationship between microstructural properties and magnetic ones of the ferromagnetic materials, the application potential of the magnetic Barkhausen noise (BN) method to non-destructive testing is constantly growing. However, the stochastic nature of the Barkhausen effect requires the use of advanced signal processing methods. Recently, the need to apply time-frequency (<i>TF</i>) transformations to the processing of BN signals arose. However, various <i>TF</i> methods have been used in the majority of cases for qualitative signal conditioning and no extensive analysis of <i>TF</i>-based information has been conducted so far. Therefore, in this paper, the wide analysis of BN <i>TF</i> representation was carried out. Considering the properties of <i>TF</i> transformations, the Short-Time Fourier Transform (STFT) was used. A procedure for definition of the envelopes of the <i>TF</i> characteristic was proposed. To verify the quality of extracted features, an analysis was performed on the basis of BN signals acquired during stress loading experiments of steel elements. First, the preliminary experiments were processed for various parameters of the measuring system and calculation procedures. The feature extraction procedure was performed for different modes of <i>TF</i> representations. Finally, the distributions of <i>TF</i> features over the loading stages are presented and their information content was validated using commonly used features derived from time <i>T</i> and frequency <i>F</i> domains.
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