SPECIAL FEATURES OF MAGNETIC PULSE HARDENING PROCESSING OF STEEL CYLINDRICAL PRODUCTS OF VARIABLE CROSS-SECTION

Abstract

The calculations of the magnetic field induction and the magnetic field intensity were carried out by the Finite Element Method (FEM) with the use of the software FEMM. The cylindrical inductor of the Magnetic-Pulse Installation (MPI) generates the magnetic field near the surface of the cylindrical steel product as of the uniform as well as variable cross section. It is shown that the regions of the products of the complex cross-section located at the minimal distance to the helix inductor are exposed to highest level of hardening. It is necessary to increase the current pulse in the inductor or to use a split inductor with the variable inner diameter repeating the product profile for hardening of the product regions located at large distances from inductor. The side surfaces of protrusions that are perpendicular to the axis of the system are not exposed to hardening due to the low gradient of the energy density of magnetic field near its surface. In the case of close proximity of the protrusions (for distance less than 1 cm), the material on the product surface in the space between protrusions is not exposedto sufficient hardening.

Keywords

• steel products
• uniform cross section
• variable cross section
• magnetic-pulse processing
• the magnetic induction vector
• the magnetic field intensity vector
• the magnetic field lines