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EXPLOSIVEE WELDING OF LARGESIZE SHEETS: SEAM QUALITY ISSUES O.L. Pervukhina, T.A. Shishkin, I.V. Denisov, and L.B. Pervukhin (Russia) Institute of Structural Macrokinetics and Materials Science RAS (ISMAN), Academician Osipyan str., 8, Chernogolovka, Moscow Region, 142432, RUSSIA Methods of testing the quality of the resulting explosion welding seam Ultrasonic testing Experimental study of wave generation We explored the quality of explosive welding of steel (09G2S) to titanium alloy (VT1-0) carried out at –15C with large sheets 31.5(26 + 5.5) 3300 3700 mm in their dimensions. Metallographic specimens 25 and 100 mm wide were cut from the welded sheet at a pitch of 300 mm; Measuring the size of the waves was performed using the magnifying glass Brinell. The pull strength of the seam was found to vary between 210 and 350 MPa Sheets elongation and Wavy structure of weld seam as a function of sheet length L wave height Sheets elongation repers L, mm = 0.12 . . .0.24 mm L, mm The sample for the study The results of ultrasonic testing 8000 mm stable wave structure h = 0. . .1 mm h = 0.12 . . .0.24 mm The size of the shock-compressed gas area / sheet length 0.40000 0.35000 0.30000 0.25000 l, м shock-compressed gas area, m 12900 s 0b l 0.20000 0.15000 1b 2 0.10000 s vк 2 2 P11 1 1 2 1 0.05000 0.00000 0.0 1.0 2.0 3.0 4.0 5.0 S, м 6.0 7.0 8.0 9.0 10.0 11.0 sheet length, m ρ0 – density of flowing gas, b – length of the contact line, P1 – pressure in the shock-compressed gas, Vк – contact point velocity, - velocity of the gas, l - extent of the zone of shock-compressed gas, s – distance from the contact point Investigation of the structure of the cladding sheet defective portion 2 layer bright, brilliant plastic 1 layer dark fragile 1 layer microstructure 1 2 3 4 C 5.31 6.01 3.42 2.13 O Na 22.60 37.08 2.00 41.64 1.45 43.10 Al Si Cl Ti 1.06 1.05 0.44 0.86 2.31 1.41 1.30 1.19 Cr Mn 7.06 1.05 3.44 1.02 1.21 0.71 Fe Ni 52.41 9.01 47.25 1.04 48.54 52.86 2 layer microstructure 2 layer microstructure O Al Si Cr Mn Fe Ni Total 1 0.61 0.59 0.42 7.17 1.23 86.78 3.20 100.00 2 1.30 1.81 1.11 92.97 0.24 100.00 0.84 1.73 Сonclusions • If the length of the field of shock-compressed gas increases the heating time of welded surfaces. This leads to rapid melting of the welded surfaces and halting the wave formation.