PSI - Issue 36

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Victor Shapovalov et al. / Procedia Structural Integrity 36 (2022) 262–268 V. Shapovalov, I. Protokovilov, V. Porokhonko / Structural Integrity Procedia 00 (2021) 000 – 000

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Table 1. Chemical compositions of used materials.

Content, wt. %

Component

Ti

Al

V

Zr

Fe

Si

O

N

H

Base metal 0,15 0,042 0,18 0,008 0,0022 Consumable nozzle 89,59 5,49 4,17 0,003 0,06 0,115 0,09 0,005 0,0029 Welding wire 90,93 3,99 3,02 1,55 0,07 0,083 0,05 0,018 0,0022 89,68 6,11 3,65 0,01

The welded joints were subjected to radiographic inspection on a RAP 150/300 apparatus. The transmission parameters were: anode voltage 250 kV, anode current 10 mA, exposure time 8.5 minutes, distance 500 mm. The sensitivity of the radiographic control was 1 mm.

Fig. 2. Schematic view of the ESW process of 100-mm-thick titanium slabs.

The chemical composition of the metal was determined by the method of Inductively coupled plasma mass spectrometry. Mechanical property tests included tension and U-notch Charpy impact (KCU) tests at room temperature. After impact strength testing, the samples were subjected to fractographic analysis. Brinell hardness was determined with a ball diameter of 10 mm and a load of 3 tons. Vickers microhardness testing was carried out at a load of 100 g. Metallographic studies were performed under a microscope "Neophot 32". To detect the structure, the samples were etched in a solution containing HF+HNO 3 +H 2 O in equal proportions. In all cases, the study was carried out on the metal of the three main zones of the welded joint: the base metal,

HAZ, and the weld metal. 3. Results and discussions

The view of the welded joints is shown in Fig. 3. The weld surface was of good quality without oxidized areas. No surface defects (pores, lack of fusion, undercutting, cracks) were found. Radiographic inspection also showed the absence of internal discontinuity flaws in the weld metal. The results of the chemical analysis of the weld metal are shown in Table 2. The data obtained show that the content of Al and V in the weld metal corresponds to the typical values for the Ti-6Al-4V alloy (5.3-6.8 % Al and 3.5-5.3 % V). In addition, the weld metal contains 0.54% Zr. This is due to the presence of this component in the used welding wire (Table 1), added to alloy to improve the mechanical properties of the welded joint.