Shejchenko G. The creation economically alloed corrosion-resistant metastable austenitic-ferrite steels and control of their properties

The object - new economically alloyed corrosion-resistant steels by austenitic-ferrite class with metastable austenite. The purpose - creation austenitic-ferrite steels on a basis of complex explorations of influence of an alloy building, conditions of a heat treatment on phase composition, structure, phase transformations at a stressing and running of their physical-mechanical properties. Methods - quantitative metallographic, magnetometric, phase X ray diffraction assayings; a X ray spectral microanalysis of phase components; a microhardness testing of structural components, testing of mechanical properties: on a stretching, twist, the dynamic camber is model with V and U by figurative incisions; testing of corrosion resistance and calculation of corrosion indexes; mathematical treatment of outcomes explorations. Novelty - the optimum composition economically alloyed corrosion-resistant steels with heightened strength and plastic properties, impact number are developed; the regularity of a modification of kinetics deformation martensite is recognition at warp and properties economically alloyed Fe Cr Mn of steels depending on an original phase relation between an amount austenite and ferrite; effects of stabilization and destabilising of austenite in austenitic-ferrite steels after a heat treatment for the first time are defined at different temperature-time parameters and the broad possibilities of regulating of a degree metastability austenite for management of their properties are shown. The outcomes - the properties of designed steel do not yield known expensive of chrome-nickel analogs; is shown proof, that by a modification of temperature-time parameters of a hardening, hyperthermal thermocyclic treatment, the age-hardenings and subzero treatments are possible in rather broad breaking points are to regulated by a phase relation between ferrite and austenite, to influence a degree of a deformation metastability austenite in chrome-manganese steels of austenitic&ferrite class and to control by a complex of their physical-mechanical properties; the calculated sample piece of a construction of pumps parts with usage of a finite element method for exploration of stress-deformed state from operation of external loads is developed, which one allows to realize prior calculation and to install regularities of a development deformation of martensate transformation at maintenance of real details. An intrusion - JSC „Production Plant “Uzhgidromash” with economic benefit more than 240 thousand UAH. Branch - mechanical engineering.