Texture formation and residual stresses into surface layers of VT8 alloy targets during irradiation by intense pulsed electron beams

Abstract

The experimental results to the effect of irradiating conditions by intense pulsed electron beams on texture and residual stresses formation in the surface layer of targets from VT8 titanium alloy are analyzed. These data have great practical significance because the blades and disks of VK-2500 helicopter engine compressors are produced from this material. The information on texture formation and residual stresses in the surface layer allows to determine service properties (fatigue resistance and heat-resistance) of parts from this material. It is shown that intense pulsed electron beam of microsecond duration is high effective tool for modification of compressor and turbine blades from VT8 alloy. It allow to realize high speed heat treatment (hardening), recrystallization of material in the surface layer with thicknesses of 20...30 µm, purification and burnishing of surface. It is possible to form in the surface layer tensile or compressive residual stresses and compressive or tensile textures depending upon energy density in pulse in the surface layer of VT8 targets. Compressive residual stresses are formed during irradiation at low energy density in pulse (lesser 20 J/cm2 ). Microdefects with craters form are not formed at these irradiation regimes that is absence of stress concentrates.