Regulations of local deformation strengthening of tubular products made of structural steel during the formation of grooves by cold plastic deformation

Abstract

The work is devoted to the study of the formation of stress concentrators on the inner surfaces of "tube"-type parts, the main function of which is to ensure the minimum consumption of fracture energy under the influence of tensile loads. The work shows the effectiveness of the application of deforming broaching (stitching) and technological lubricant specially developed for forming stress concentrators under the action of high contact loads, which are accompanied by deformation. The patterns of deformation hardening of the material during the formation of longitudinal grooves on the inner surfaces of parts such as bushings by deforming broaching are studied. At the qualitative level, the influence of technological parameters of the process on the distribution of microhardness along the depth of the wall of the processed part and along the cross-section profile of the tool was established. The identified regularities can be used in the design of technological operations of forming grooves by methods of cold plastic deformation and correction of technological regimes based on the requirements for mechanical characteristics that ensure the efficiency of product use. The studied regularities are valid for forming grooves in tubular products made of structural steels with a hardness in the range of HB 110-200.

Keywords

• cold plastic deformation
• forming
• contact zone
• strengthening
• groove
• tube
• distribution of microhardness