The article presents an analysis of changes in the physical properties of the surface layer after the turning process of difficult-to-machine materials using LFV (Low Frequency Vibration) technology. This technology introduces additional, periodic low-frequency vibrations along the tool feed axis, which are precisely synchronized with the rotational movement of the spindle. The effect of this synchronization is periodic interruption of the tool contact with the material, which leads to cyclic detachment of the chip and the formation of its segmented structure. From a physical point of view, the variable cross-section of the deformed material results in local fluctuations of stresses and temperature, which affects the nature of structural changes in the surface layer of the machined material. The paper analyzes how LFV vibration parameters - such as frequency, amplitude and their synchronization with the spindle rotation - affect the surface morphology and functional parameters of the surface layer, determined, among others, on the basis of the analysis of the material share curve. Experimental studies were carried out on four materials with different physical and structural properties: 1.4404 stainless steel, S235 structural steel, CW004A electrolytic copper and EN AW-6060 aluminium alloy.