Abstract
Cold-drawn metal has a number of undeniable advantages over the hot-rolled one. Increased hardness, high surface quality, stability of the diametrical dimension along the length of the workpiece are the basis for choosing calibrated metal as effective workpieces for the manufacture of long parts such as shafts, axles, and rods. In some cases, such workpieces require a small amount of machining, for example, threading or making necks at the ends of a bar. The wider use of the calibrated metal is hindered by residual stresses that are formed during its manufacture. In the first part of this article, it was proposed to use small plastic deformations to control residual stresses. By the example of a new process of surface plastic deformation, which is called orbital burnishing, the working and residual stresses in cylindrical workpieces are determined. In the second part of the article, the process of enveloping surface plastic deformation is considered, which, at high productivity, makes it possible to reduce the residual tensile stresses in the calibrated metal or form the surface layers of the workpiece compressive stress. A technique for the experimental determination of residual stresses in the volume of a body is based on layer-by-layer removal of the inner and outer layers of cylindrical samples. Influence of the main parameters of the enveloping deformation process on the components of the residual stress tensor is established. A range of relative compressions (0.1 – 1.0 %) is revealed, at which residual compressive stresses are formed in the surface layers of the workpiece. It was found that at a relative compression of 0.5 %, the maximum residual compression stresses are created. Enveloping surface deformation has a positive effect on the residual stress state and on colddrawn metal – the residual tensile stresses can be reduced, removed or converted into compressive ones.
Highlights
The enveloping deformation process on the components of the residual stress tensor is established
Enveloping surface deformation has a positive effect on the residual stress state and on colddrawn metal – the residual tensile stresses can be reduced, removed or converted into compressive ones
Таким недостатком является нестабильность геометрической формы цилиндрических прутков, которая проявляется в их искривлении и поводках
Summary
Влияние охватывающего поверхностного деформирования на остаточные напряжения в цилиндрических прутках. На примере нового процесса поверхностного пластического деформирования, который назвали орбитальным выглаживанием, определены рабочие и остаточные напряжения в цилиндрических заготовках. Во второй части статьи рассматривается процесс охватывающего поверхностного пластического деформирования, который при высокой производительности позволяет снижать остаточные напряжения растяжения в калиброванном металле или формировать в поверхностных слоях заготовки напряжения сжатия. Установлено влияние основных параметров процесса охватывающего деформирования на компоненты тензора остаточных напряжений. Выявлен диапазон относительных обжатий (0,1 – 1,0 %), при котором в поверхностных слоях заготовки формируются остаточные напряжения сжатия. Положительное влияние на остаточное напряженное состояние оказывает охватывающее поверхностное деформирование и на холоднотянутый металл – остаточные напряжения растяжения можно уменьшить, снять или преобразовать в сжимающие. Влияние охватывающего поверхностного деформирования на остаточные напряжения в цилиндрических прутках // Известия вузов.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.