Nesterov O. Increasing of stability metalworking instrument by plasma surface processing. .

The dissertation contains theoretical and experimental research of process plasma surface processing to instrumental steels. The object of study - instrumental steels of metalworking instrument under plasma processing. The subject of study - determination of optimum technological modes complex volume plasma processing, including volume quenching with use the non-standard temperature intervals and plasma surface processing, executed on optimum modes; working characteristics instrumental steels after complex processing; influence of location of plasma stream on form and sizes of HAZ; and influence of degrees of hardening mechanisms action on structured conversions and characteristics of instrumental steels. The main methods of studies in dissertation work - mathematical modeling, founded on laws heat conductivity; x-raying analysis of phase composition and parameters of crystalline lattice; metallographic analysis of structures; and mechanical testing under steady and dynamic loading. When use the heat-conductivity theory is designed strategy of calculation of parameters of thermal cycle and optimum modes plasma processing the instrument along worker of edge. Given strategy has allowed to realize the optimisation of technological variants of plasma surface processing of the instrument and to getthe optimum combination of the strengthening zone geometric parameters. On the grounds of metallographic studies are installed the phase and structured conversions in instrumental 3steel under complex volume plasma processing, containing volume hardening from the temperature, different from standard, and plasma surface processing, executed on optimum modes. Studied nature of action and level of different mechanisms hardening on reached level of working characteristics instrumental become under complex volume plasma processing. The method of determination of local mechanical characteristics (toughness, ductility) has been developed, allowing define quantitative features of characteristics in separate areas composite hardened layer. On the grounds of studies is designed the scientific bases of complex processing technology of the instrument, which provides simultaneous increasing as hardness and heat-resistances, so toughness and plasticity hardened layer. There are offered and introduced in production technological processes of complex volume plasma processing of the metalworking instrument. .