Bauschinger effect during alternating deformation

Abstract

The Bauschinger effect is a phenomenon of a decrease in material resistance to small plastic deformations after preliminary plastic deformation of the opposite direction, discovered in 1881. This effect is of great importance and is used, in particular, in studying the fatigue strength of materials under alternating loads. The Bauschinger effect is inherent in all metals and alloys, although it is most pronounced in steels. Therefore, it is one of the factors affecting the quality of finished metal products subjected to alternating loading during manufacture. This review analyzes the literature data on the problem of the Bauschinger effect in the case of alternating deformation of metals. Various mechanisms explaining the Bauschinger effect are briefly considered. The factors that qualitatively and quantitatively affect the Bauschinger effect are described in detail, namely the degree of preliminary deformation, composition, structure and properties of the material, deformation conditions, the phenomenon of dynamic deformation aging, and temperature. The problem of the Bauschinger effect in the case of alternating deformation of steel products is considered, in particular, in the production of oil and gas pipes of large diameter. Various methods and approaches to the evaluation and quantitative measurement of the Bauschinger effect are described; the dependence of the Bauschinger parameter on the value for residual deformation is shown. It is concluded that the Bauschinger effect plays both a positive and a negative role in the production of metal products, in particular oil and gas pipes. On the one hand, the Bauschinger effect has a negative effect, reducing the level of mechanical properties of the final product below the required one. On the other hand, it creates a certain margin of plasticity of the deformable material in the process of forming and laying pipes.