Review article

The paper deals with the issues of the influence of the structure parameters of structural steel on the assessment results of intense stress and strain state of construction machines` welded metalwork. It is shown that the key parameters at determining the strength and magnetic properties of ferromagnetic materials are the grain size, density of dislocations, existence of the substructure, impurities and disperse particles, cementite form, the nature and quantity of the alloying elements. It is established that a prerequisite for applying the magnetic control for the purpose of assessing the stress and strain state of welded metalwork is existence of correlation links between the initial metal structure, mechanical and magnetic properties of metals with positive magnetostriction. Examples of using the probe-coil magnetic field testing method are given.