scholarly journals Development of heat treatment modes for a two-phase titanium alloy to form regulated structure and properties complex

2019 ◽  
Vol 298 ◽  
pp. 00049
Author(s):  
Svetlana Skvortsova ◽  
Galina Gurtovaya ◽  
Maria Afonina ◽  
Natalya Ruchina ◽  
Gulnara Zaynetdinova

The article shows the possibility of creating structure of the same type and, accordingly, a close level of properties in hot-rolled semi-finished products of the VST2K alloy with different chemical composition by means of heat treatment.

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4415
Author(s):  
Yuri Shchitsyn ◽  
Maksim Kartashev ◽  
Ekaterina Krivonosova ◽  
Tatyana Olshanskaya ◽  
Dmitriy Trushnikov

The paper deals with the main formation patterns of structure and properties of a titanium alloy of the Ti-6Al-4V system during additive manufacturing using cold metal transfer (CMT) wire deposition. The work aims to find the optimal conditions for layer-by-layer deposition, which provides the high physical and mechanical properties of the titanium alloy of the Ti-6Al-4V system hybrid, additively manufactured using CMT deposition. Particular attention is paid to interpass forging during the layered printing of the product. Additionally, we investigate how the heat treatment affects the structure and properties of the Ti-6Al-4V alloy that has been CMT-deposited, both with and without forging. These studies have shown that the hybrid multilayer arc deposition technology, with interpass strain hardening, allows the use of high temperature and high technology titanium alloys to obtain products of a required geometric shape. It has been proven that the interpass deformation effect during CMT deposition contributes to a significant decrease in the sizes of the primary β-grains. In addition, forging enhances the effect of microstructure refinement, which is associated with phase recrystallization in deformed areas. It is shown that the heat treatment leads not only to a change in the morphology of the phases but also to additional phase formations in the structure of the Ti-6Al-4V-deposited metal while the mechanism is realized and consists of the gradual decomposition of the martensitic α′-phase and the formation of a dispersive α2-phase. This structure formation process is accompanied by the dispersion hardening of the α-phase. The strength characteristics of the Ti-6Al-4V alloy obtained using layer-by-layer CMT with forging are given; they exceed the strength level of materials obtained with the traditional technologies of pressure treatment, and there is no decrease in plasticity characteristics. The use of the subsequent heat treatment makes it possible to increase the ductility characteristics of the deposited and forged Ti-6Al-4V material by 1.5–2 times without strength loss.


2017 ◽  
Vol 265 ◽  
pp. 785-788
Author(s):  
A.V. Zhelnina ◽  
A.G. Illarionov ◽  
M.S. Kalienko

VST5553 titanium alloy is high strength (α + β) - transition alloy which is used for the production of heavy-duty parts [1]. It is known [2], that the cooling rate changing during the heat treatment can change the phases ratio in the alloy. With regards to the VST5553 alloy, this may be due to different cooling rates over the cross section of large-sized semi-finished goods. This in turn affects a complex of properties. Thus, it is necessary to know the effect of the cooling rate of two-phase region on the structure and properties, particularly the VST5553 alloy. However, the research in this area is not sufficient enough. The present study is devoted to this issue.


2016 ◽  
Vol 25 (3) ◽  
pp. 734-743 ◽  
Author(s):  
Jianwei Xu ◽  
Weidong Zeng ◽  
Zhiqiang Jia ◽  
Xin Sun ◽  
Yawei Zhao

2015 ◽  
Vol 788 ◽  
pp. 187-193 ◽  
Author(s):  
Aleksandr Prudnikov ◽  
Marina Popova ◽  
Vladimir Prudnikov

The results of the influence of preliminary thermal cyclic deformation and subsequent hardening heat treatment on the microstructure and mechanical properties of hot-rolled sheet steel 10 are presented. It is shown that the use of preliminary thermal cyclic deformation of the steel 10 stock material results in a fine-grained structure of a hot-rolled sheet (3 mm thick) produced by an industrial technology. Deformation occurred at a temperature above AC3 (1250 °C), with cooling to 200-300 °C during 10 cycles and the deformation ratio per cycle being 6-8 %. Such a treatment before sheet hot-rolling allows increasing the strength characteristics (tensile strength, yield strength) by almost 30 %. It has been established that the use of subsequent heat treatment (quenching, 900 °C, water and tempering 1 h, 600 °C) leads to a further increase in strength characteristics by 15-20% while maintaining a sufficient level of ductility of sheet steel.


2021 ◽  
Vol 1032 ◽  
pp. 152-156
Author(s):  
Peng Lei ◽  
Shu Cheng Dong ◽  
Guang Yu Ma ◽  
Tuo Cheng ◽  
O.M. Ivasishin

TC16 titanium alloy is a martensite α+β two-phase high strength titanium alloy, which can improve its structure and enhance properties through heat treatment. Effect of annealing process on microstructure and tensile properties of TC16 titanium alloy was investigated using optical microscope, scanning electron microscope and universe tensile test machine. The results show that when annealed at 720°C for 4h then furnace cooling to ambient temperature, the tensile strength of the TC16 alloy reaches nearly 900MPa,the elongation reaches 19.6% and the reduction of area reaches 65%, which present a good comprehensive performance.


Tribologia ◽  
2017 ◽  
pp. 65-71 ◽  
Author(s):  
Aleksandra PERTEK-OWSIANNA

The purpose of the paper was to test how the content of carbon and alloying elements in steels influence the structure and properties of boronized layers. The following grades of steels were used during the tests: C45, C99U, 41Cr4, 42CrMo4, 45SG, 50HS, 60G, and 102Cr6. In the process of boronizing, the two-phase layer of borides of FeB and Fe2B were obtained on the tested steels with a hardness from 1900 HV0.1 for boride FeB to 1600 HV0.1 for Fe2B, irrespective of the chemical composition of the core/substrate. As the kontent of carbon and alloying elements in steels increase, the structure of borides becomes more compact, and the needles are thicker. The richer in alloying elements the core and the more carbon in steel, the thinner is the boride layer. After boronizing, the layer of FeB and Fe2B with a thickness of approx. 110 μm for C45 steel to approx. 90 μm for 102Cr6 steel was obtained. The test results indicate that the brittleness of borides increases in steels with the addition of Cr, and it decreases in steels containing Si and Mn. The highest wear resistance was obtained in steel 102Cr6.


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