Ti-6Al-4V (Ti Grade 5) alloy Argon Arc Welding Process

Ti-6Al-4V (Ti Grade5) is an (α+β) type titanium alloy. Ti-6Al-4V titanium alloy has excellent corrosion resistance, low density, high specific strength, good toughness and weldability, and a series of other advantages. Ti-6Al-4V has moderate room temperature and high-temperature strength, good thermal stability and weldability, and is suitable for manufacturing aerospace components that operate for long periods at 450 degrees (6000 hours) and 650 degrees (3000 hours). The argon arc welding, contact welding and submerged arc welding of this alloy have good welding performance, and the room temperature and high-temperature strength of the weld seams are 90%-95% of the base material strength.

The industrial titanium automatic argon arc welding process specifications are determined by selecting the number of welds, welding current (/), arc voltage (U), welding speed (V), argon gas flow (>), etc., based on the thickness of the sheet. Select a 1.5mm thick sheet and adopt the automatic argon arc welding process specification without adding welding wire for a single weld. The mechanical properties of the automatic argon arc welding butt joint of industrial titanium plates were studied. The tensile strength (crb), strength coefficient (r) and bending angle (a) of the welded plate joints were tested. When industrial pure titanium is used in the manufacturing of non-bearing structural components in aerospace, the long-term working temperature can reach 300 degrees. Therefore, the high-temperature performance at 300 degrees and 400 degrees was also tested.

In addition to argon arc welding and electron beam welding, Ti-6Al-4V can also be welded by various forms such as submerged arc welding, penetration welding, double-sided double-arc dynamic welding, resistance welding and brazing. Submerged arc welding can weld several millimeters (65mm) thick plates through one weld. Penetration welding can be used to weld the T-shaped joint plate from the backside of the T-shaped joint plate, forming both sides of the T-shaped joint in one weld, with high welding efficiency and quality. Before welding titanium plates, bevels should be made according to the plate thickness: 2.5mm and below leave a joint of 0-0.5; 15mm and below make a single-sided bevel; 10-30mm make a double-sided bevel. www.lh-ti.com It is very important to clean the welding wire and the welded piece before welding, and the requirements are extremely strict. During welding, to prevent deformation, 100-150 positioning welds are required, and the argon gas should be of first-grade pure argon (the pressure in the argon cylinder is less than 0.981 MPa when it is stopped). The welding wire material should be as close as possible to the welded piece (or a narrow strip can be cut from the welded piece for substitution), and attention should be paid to the color change in the heat affected zone during welding (silver-white, golden, good; dark blue, dark gray, poor) as it directly affects the joint performance. Ti-6Al-4V plates can also be welded with other titanium alloys. The automatic argon arc welding joint of a 2mm thick plate has little difference in strength, bending angle and impact performance in its welding state and after 100 hours of heat exposure at 450 degrees. The joint is insensitive to heat treatment.