Investigation of the stability of a technological system in combined processes of thermomechanical treatment

Consideration is given to combined thermomechanical methods of surface formation: rotational cutting with plasma heating and surface plastic deformation of a coating in electromagnetic welding. Unstable states of a technological system are investigated. Ways of controlling the stability and enhancing the efficiency of the combined methods of thermomechanical treatment are outlined.Notation V₁ andV₂ volumes of the ingot and the workpiece respectivy - Re=vt/v Reynolds number - Pr=v/gw Prandtl number - Pe=vt/ Peclet number - v rate of treatment - t treated layer thickness - v and coefficients of kinematic viscosity and thermal diffusivity - S feed rate - v resultant velocity of motions - _z and _xz stresses of the treated material in the direction of the main motionv and in the direction of the moment of shaping that takes account of the interdependence of the motionsv andS [1] - _y and _yz stresses of a ferropowder medium in the direction perpendicular to the surface formed and in the direction of rotation on a plane perpendicular to it [2] - ^* and specific electrical conductivity and electrical resistance of the powder medium - Ra mean arithmetical deviation of the profile of the microrelief of the surface - Q welding efficiency (the increase in the coating mass) - HRC_e Rockwell hardness - B magnetic induction - I current strength - L distance from the heating source to the tool - K=v_r/v kinematic coefficient of the rotational tool - v_r self-rotational speed of the tool - P forces of deformation of the surfaceBelarusian Agrarian Technical University, Minsk. Polotsk State University, Novopolotsk. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 68, No. 4, pp. 598–604, July–August, 1995.