Features of Intermetallic Formation in the Solid Phase on a Steel–Titanium Bimetal Interface under the Conditions of Arc Welding

The object of this study is the formation intermetallic phases (IMPhs) in heat-affected zone (HAZ) joints steel–titanium bimetal plates produced by arc welding. A titanium layer (2 mm) was welded plasma method (PAW), a barrier Cusi3Mn1 bronze deposited on it TIG method, first steel CMT, and Puls-MAG used for filling groove. Here, heating solid phase takes place HAZ, which may lead to undesirable brittle IMPhs further joint failure. Mathematical modeling performed metallurgical features formed during processes HAZ were studied identify risk IMPh formation. It found that at temperature increase from 900 1450 °C, continuous interface, contained FeTi IMPh, width increased 1 10 μm. In range 1300…1430 an TiFe2-type additionally side. 1430…1450 TiFe2 replaced TiXFe phase, both side This consists intermetallics (73–75% Ti + 27–25% Fe) (80–85% 20–15% Fe), close Ti2Fe-type phase. interlayer intermetallics, temperatures 900…1300 has morphology (HV0.01–650…690). At rising above 1300 became more ramified (HV0.01–590…610) because larger number pores microcracks within it. 900…1450 solid-phase diffusion proceeded near interface two metals. iron diffusion, 5–10 μm 40–60 width, titanium. steel, 15–20 120–150 formed, starting °C higher. recommended perform industrial welding modes, heat input equal 200…400 J/mm. period 10–12 s, 1.5–3.5 mm 900–1150 °C. promotes FeTi-type up 1–2 width.