Electron beam surfacing of carbide steels 1. Special features of surfacing technology and preparation of composite surfacing mixtures

摘要

The proportion of structures, installations and equipmentnapproaching the critical service life or already passednthe design life is rapidly increasing in a number of areasnin industry (power engineering, transport, chemical,npetrochemical) . On the other hand, the newly introducednequipment is produced from efficiently alloyed lowncarbon structural steels in order to reduce the expenditurenon material. The application of these materials requiresnsurface hardening. Thus, in the current conditions, thenprimary task is the reliable hardening of working surfacesnof machines and mechanisms.nHardening technologies using high-energy methods arenused on an increasing scale. The effect of concentratednenergy fluxes (CEF) results in superfast heating (upnto 1012 K/s), melting, evaporation and superfast (up ton1010 K/s) solidification of the material. These processesnmake it possible to form, in the surface layer of thenmetal, amorphous and nanocrystalline structures andnalso metastable phases which cannot be produced innthe conventional technological processes. The principalnchanges in the structural-phase state of the surface layersnimprove the mechanical and physical properties of thenmaterial. Therefore, these methods of modification ofnthe surface of metallic materials represent a promisingndirection of modern materials science.