| 2013 №02 (03) | 2013 №02 (05) |
The Paton Welding Journal, 2013, #2, 20-23 pages
INFLUENCE OF LOCAL HEAT TREATMENT AT EBW OF TITANIUM ALLOYS WITH SILICIDE STRENGTHENING ON MECHANICAL PROPERTIES OF WELD METAL
E.L. VRZHIZHEVSKY, V.K. SABOKAR, S.V. AKHONIN and I.K. PETRICHENKO
E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
Abstract
Disadvantages of EBW of complex-alloyed titanium alloys include high rates of weld metal heating and cooling, leading to lowering of ductility properties. Research objective consisted in determination of the influence of preheating and local heat treatment by the electron beam on prevention of formation of defects in the form of cracks and improvement of ductility properties of welded joints of high-temperature titanium alloys. Research purpose was determination of preheating temperature to prevent the negative influence of high temperature gradient characteristic for EBW. In this case a smoother temperature gradient in welding is ensured that prevents cracking. After welding the joints were subjected to local annealing at the temperature of 900 °C for 10 min. All the welded joints were subjected to X-ray testing and metallographic examinations. It was revealed that varying the heating parameters at local heat treatment by the electron beam allows controlling the rate of phase and structural transformations in titanium alloys with silicide strengthening and, thus, changing the structure and, therefore, also the properties of welded joints that allows storing the welded structures for a long time before conducting total furnace treatment. The proposed approach can be used in manufacture of axial-flow compressors for gas turbine engines and power units. 6 Ref., 1 Table, 7 Figures.
Keywords: electron beam welding, complex-alloyed titanium alloys, weld metal, local heat treatment, mechanical properties, prospects for application
Received: 18.10.12
Published: 28.02.13
References
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