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8. Effect of process parameters of selective laser melting on the structure, texture, and mechanical properties of an alloy based on orthorhombic titanium aluminide Ti2AlNb.

Author

Illarionov, A. G., Demakov, S. L., Stepanov, S. I., Karabanalov, M. S., Lugovaya, K. I., Shabanov, M. A., and Popov, A. A.

Abstract

The impact of selective laser melting (SLM) process parameters on the porosity, microstructure, phase and chemical composition, texture, and physical-mechanical properties of orthorhombic titanium aluminide Ti2AlNb (O-alloy) powder was studied using a range of methods, including hydrostatic weighing, scanning and transmission electron microscopy, X‑ray diffraction analysis, energy-dispersive X‑ray spectroscopy, microindentation, and compression testing. It was demonstrated that an increase in the volumetric energy density within the range of 28 to 139 J/mm3 led to the following effects: 1) increase in the relative density of the obtained O‑alloy from 97 to 99.9%, 2) intensification of axial texture with a pronounced 001 direction in the detected β/B2-solid solution, and 3) reduction in the Al content, increase in the Nb content, and lower enrichment with oxygen in the obtained samples. It was demonstrated that detachment from the build platform and longitudinal cutting of the O‑alloy results in the imbalance of residual stresses in samples synthesized on a platform, pre-heated at 200 °C, which is accompanied by the formation of cracks. This study considers the typical structural defects of the alloy, including pores, lack of fusion, and chemical heterogeneity, which are observed following SLM. A series of physical-mechanical properties of the synthesized O‑alloy samples were determined, including Vickers hardness (390–430 HV), elastic modulus (91–98 GPa), compressive yield strength (1060–1080 MPa), and compressive strain (of at least 30%). The relationship between these properties and the structural-textural state of the obtained O‑alloy samples is discussed. [ABSTRACT FROM AUTHOR]

Published
2024
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11. Effect of Temperature and Rate Treatment Parameters on the Structural Phase State and Properties of Ti2AlNb Titanium Aluminide-Based Alloy.

Author

Demakov, S. L., Vodolazskii, F. V., Illarionov, A. G., Shabanov, M. A., and Karabanalov, M. S.

Subjects
TITANIUM alloys, TEMPERATURE effect, INTERMETALLIC compounds, HEAT resistant alloys, MODULUS of elasticity, DIFFERENTIAL thermal analysis
Abstract

Abstract—Differential thermal analysis, scanning electron microscopy, X-ray diffraction analysis, and microindentation are used to study changes in the structure, phase composition, microhardness, and contact modulus of elasticity of a heat-resistant alloy based on the Ti2AlNb titanium intermetallic compound, depending on the rate of colling (10–80°/min) from heating temperatures of 950 and 970°С. Using the results obtained, thermokinetic diagrams of high-temperature decomposition of the β(B2) solid solution are constructed. [ABSTRACT FROM AUTHOR]

Published
2024
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17. Alloys Based on Orthorhombic Intermetallic Ti2AlNb: Phase Composition, Alloying, Structure, Properties.

Author

Illarionov, A. G., Demakov, S. L., Vodolazskiy, F. V., Stepanov, S. I., Illarionova, S. M., Shabanov, M. A., and Popov, A. A.

Subjects
HEAT resistant alloys, ALLOYS, TITANIUM alloys, HEAT treatment, MANUFACTURING processes, PHASE diagrams, PHASE transitions
Abstract

The article analyses data for chemical composition, manufacturing and processing methods for promising heat-resistant alloys based upon orthorhombic titanium intermetallic Ti2AlNb (O-alloys) developed within Russia and abroad. Phase diagrams typical for alloys based upon Ti–Al–Nb and general data for the phases formed in these alloys are provided. Concepts of aluminum and niobium equivalents used for multicomponent alloys are considered. The effect of alloying elements on a combination of mechanical properties of O-alloys, alloying principles, and compositions of the alloys developed are summarized. Characteristics of phase transformations occurring within alloys during heat treatment, including continuous heating and isothermal treatment, are provided. Typical microstructures of the alloys are presented; processing methods for their production and the influence of structural parameters on a combination of properties are described. Methods for manufacturing and processing routes of O-alloys are presented, which provide a good set of properties at room and elevated temperatures, as well as possible operating temperatures for refractory use. [ABSTRACT FROM AUTHOR]

Published
2023
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45. Influence of Heat Treatment Regime on Structure, Phase Composition and Hardness of Alloy VTI-4

Author

Vodolazsky, F. V., Demakov, S. L., and Shabanov, M. A.

Subjects
STRUCTURE, ФАЗОВЫЙ СОСТАВ, ОХЛАЖДЕНИЕ, 2-PHASE, 2-ФАЗА, ФАЗА, COOLING, PHASE, TI–21AL–23NB, ИНТЕРМЕТАЛЛИДНЫЙ СПЛАВ, РСФА, INTERMETALLIC ALLOY, СТРУКТУРА, XRDA, PHASE COMPOSITION, TI2ALNB
Abstract

In this work, we studied the structure, phase composition, and hardness of the Ti–21Al–25Nb–1V intermetallic alloy (at. %) When heated to temperatures of 920 and 940 °C with preliminary heating to 1060 °C and 800 °C. It was established that the phase composition is represented by O- and β-phase. В данной работе проведено исследование структуры, фазового состава и твердости интерметаллидного сплава Ti–21Al–23Nb–1V (ат. %) при нагреве на температуры 920 и 940 °C с предварительным нагревом до температуры 1060 °C и 800 °C. Установлено, что фазовый состав представлен О- и β-фазой.

Published
2020

46. Effectc of Deformation on Evolution of Ortorombic Martensite Lattice Periods in Titanium Alloy

Author

Demakov, S. L., Koemets, O. A., Oleneva, Yu. N., and Коэмец, O. A.

Subjects
TITANIUM ALLOY OF MARTENSITE CLASS, ORTHORHOMBIC MARTENSITE, XPDA, ОРТОРОМБИЧЕСКИЙ МАРТЕНСИТ, LATTICE PERIOD, ТИТАНОВЫЙ СПЛАВ МАРТЕНСИТНОГО КЛАССА, ПЕРИОД РЕШЕТКИ, РФСА
Abstract

The study was carried out by methods of XPDA and metallography the effect of deformation on the change of lattice periods of orthorhombic martensite in a hardened titanium alloy Ti-1,4Al-10,5Mo (wt. %). It was discovered that in samples hardened from critical and higher quenching temperatures of 785 °C and 850 °C, the change in the lattice periods of martensite At low degrees of deformation up to 5 % of a load occurs non-monotonically. Методом РФСА и металлографии проведено исследование по влиянию деформации на изменение периодов решетки орторомбического мартенсита в закаленном титановом сплаве Ti–1,4Al–10,5Mo (масс. %). Обнаружено, что в образцах, закаленных от критических и более высоких температурах закалки (785 °C и 850 °C) изменение периодов решетки мартенсита при малых степенях деформации (до 5 %) происходит немонотонно.

Published
2020

48. Влияние деформации на изменения периодов решетки орторомбического мартенсита в титановом сплаве

Author

Demakov, S. L., Koemets, O. A., Oleneva, Yu. N., Демаков, С. Л., Коэмец, O. A., Оленева, Ю. Н., Demakov, S. L., Koemets, O. A., Oleneva, Yu. N., Демаков, С. Л., Коэмец, O. A., and Оленева, Ю. Н.

Abstract

The study was carried out by methods of XPDA and metallography the effect of deformation on the change of lattice periods of orthorhombic martensite in a hardened titanium alloy Ti-1,4Al-10,5Mo (wt. %). It was discovered that in samples hardened from critical and higher quenching temperatures of 785 °C and 850 °C, the change in the lattice periods of martensite At low degrees of deformation up to 5 % of a load occurs non-monotonically., Методом РФСА и металлографии проведено исследование по влиянию деформации на изменение периодов решетки орторомбического мартенсита в закаленном титановом сплаве Ti–1,4Al–10,5Mo (масс. %). Обнаружено, что в образцах, закаленных от критических и более высоких температурах закалки (785 °C и 850 °C) изменение периодов решетки мартенсита при малых степенях деформации (до 5 %) происходит немонотонно.

Published
2020

49. Исследование влияния режимов термической обработки на структуру, фазовый состав и свойства сплава ВТИ-4

Author

Vodolazsky, F. V., Demakov, S. L., Shabanov, M. A., Водолазский, Ф. В., Демаков, С. Л., Шабанов, М. А., Vodolazsky, F. V., Demakov, S. L., Shabanov, M. A., Водолазский, Ф. В., Демаков, С. Л., and Шабанов, М. А.

Abstract

In this work, we studied the structure, phase composition, and hardness of the Ti–21Al–25Nb–1V intermetallic alloy (at. %) When heated to temperatures of 920 and 940 °C with preliminary heating to 1060 °C and 800 °C. It was established that the phase composition is represented by O- and β-phase., В данной работе проведено исследование структуры, фазового состава и твердости интерметаллидного сплава Ti–21Al–23Nb–1V (ат. %) при нагреве на температуры 920 и 940 °C с предварительным нагревом до температуры 1060 °C и 800 °C. Установлено, что фазовый состав представлен О- и β-фазой.

Published
2020

50. Effect of Thermomechanical Treatment Parameters on Structure, Phase Composition and Mechanical Properties of Ti-3Al-5Mo-4.5V Titanium Alloy

Author

Illarionov, A. G., Stepanov, S. I., Demakov, S. L., Illarionov, A. G., Stepanov, S. I., and Demakov, S. L.

Abstract

The structure, phase composition and mechanical properties of (α+β) - titanium alloy solution treated at 850 C, cold-rolled at the reduction ratio in the range of 0... 45%, followed by ageing at 450, 500, 550 C for 0.5, 1.5, 3 hours was studied using XRD, microindentation and tensile testing. The influence of strain level at cold rolling and time-temperature parameters of ageing on the formation of structure and phase composition of solution treated and water quenched Ti-3Al-5Mo-4.5V alloy was investigated and discussed in terms of tensile properties and microhardness. The parameters of low temperature thermomechanical treatment (LTMT) of the (α+β) - alloy were proposed to obtain a high-strength state. © Published under licence by IOP Publishing Ltd.

Published
2020

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