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Information × Registration Number 0213U003980, 0107U009636 , R & D reports Title Physical nature of structural, textural and chemical inhomogeneities and thier role in formation of physical and mechanical properties of titanium alloys. popup.stage_title Head Ivasishin Orest Mykhailovich, Registration Date 15-02-2013 Organization Institute for metal physics NAS Ukkraine popup.description2 Formation of chemical, structural and textural inhomogeneity during thermomechanical processing (TMP) and rapid heat treatment (RHT) of commercial titanium alloys of two classes (two-phase alpha+beta and metastable beta) under essentially non-equilibrium condition and synthesis were studied employing different experimental approaches. It was shown that formation on TMP of uniform and disperse globular-type microstructure is necessary condition to ensure optimal balance of mechanical properties of these alloys in both initial (annealed) and thermally-hardened states. Necessary for creation of more uniform and finest quenched microstructure thermo-kinetic condition of RHT are established for two-phase alpha+beta alloys that allow to obtain maximum strength well-balanced with ductility and fatigue. Two principal approaches and algorithms for thermo-time regimes of such treatment estimation were proposed. For metastable beta alloys physical principles and practical regimes of a new treatment based on combination of cold deformation and rapid recrystallization were developed. Also features of phase and microstructural transformations in these alloys under local (surface) RHT forming gradual structural conditions were investigated. As a result it was shown that forming controlled inhomogeneity became possible to vary physical and mechanical properties of commercial titanium alloys within a wide range and achieve them at unreachable by other methods level. Physical background for employment of titanium hydride for synthesis of alloys using heterogeneous disperse systems and its refinement against contaminations (oxygen, chlorine and carbon) was developed. It is found that chemical homogenization heterogeneous systems can be fastened by means of alpha-particles barrier effect reducing via retention of hydrogen in matrix or with substitution by balance between alloying elements in master alloys. Optimization of synthesis parameters depending on alloys' chemical composition allowed to obtain structural conditions having high balance of mechanical properties meeting requirements of standards for cast and deformed alloys. Performed with different approaches modeling of phase transformations, plastic deformation, recrystallization and grain growth allowed to establish general dependencies for these processes and showed a good agreement with experimental data. Influence of chemical and structural inhomogeneities of different scale on high-temperature creep was established for some materials.5481 Product Description popup.authors Бондарчук Вадим Іванович Гуменяк Микола Мирославович Дехтяр Олександр Ілліч Карасєвська Ольга Павлівна Квишко Михайло Федорович Костильова Тетяна Юр"ївна Марковський Павло Євгенович Матвійчук Юрій Васильович Меламед Борис Якович Моісеєва Ірина Володимирівна Моляр Олександр Григорович Піщак Вадим Каспарович Саввакін Дмитро Георгійович Теруков Андрій Вікторович Шевченко Сергій Валерійович popup.nrat_date 2020-04-02 Close