Gr1 (TA1)

The core advantage of Gr 1 (TA1) lies in its extremely high purity and very low interstitial element content. The oxygen content is strictly controlled to ≤ 0.18%, endowing the material with exceptionally high ductility (elongation ≥ 24-30%) and excellent cold formability in the annealed condition. It can undergo complex forming operations such as deep drawing, cold bending, spin forming, and bulging. Its limiting draw ratio exceeds that of 304 stainless steel, making it suitable for manufacturing complex-shaped components such as heat exchanger plates, chemical linings, bellows, titanium cups, and deep-drawn parts. This alloy has a low yield-to-tensile strength ratio (typically < 0.7) and exhibits an extremely long work hardening range after yielding. It can tolerate massive plastic deformation without rupture, making it the most ductile and soft grade in the industrial pure titanium series.

Gr 1 (TA1) exhibits exceptional corrosion resistance in numerous corrosive media, with its core mechanism being the ability to instantly form an extremely thin (several nanometers), dense, stable, and self-healing TiO₂ passivation film on its surface. In media such as seawater, chloride solutions, wet chlorine gas, nitric acid, organic acids, and alkaline solutions, its corrosion resistance far exceeds that of stainless steel and copper alloys, with an extremely low corrosion rate (e.g., almost no pitting or crevice corrosion occurs in seawater). It is one of the few metal materials capable of withstanding corrosion by wet chlorine gas, making it a core material choice for chlor-alkali industry, seawater desalination, and condensers in coastal power plants.

The density of Gr 1 (TA1) is approximately 4.51 g/cm³, which is only 57% of that of carbon steel, giving it a natural lightweight advantage. Although its absolute strength is not high (tensile strength in annealed condition: 240-370 MPa), its specific strength (strength/density) remains considerable. It is particularly valuable in applications where lightweighting is required but loads are not extreme, such as aircraft skins and structural components, ship piping, and deep-sea equipment. Its modulus of elasticity is about 105 GPa, roughly half that of steel, resulting in large elastic deformation and excellent vibration damping and impact resistance.

Gr 1 (TA1) exhibits excellent weldability and can be welded using various methods such as TIG, MIG, and plasma welding. The strength coefficient of the welded joint can reach over 90% of the base metal, making it one of the best weldable grades among titanium and titanium alloys. When welding, high-purity argon gas must be used to fully protect the high-temperature zone to prevent oxidation contamination that could lead to embrittlement. This alloy has good cold and hot working properties and can undergo forging, rolling, stamping, deep drawing, and other processes. However, its machinability is poor due to low thermal conductivity and a tendency to stick to tools. Hard alloy tools, low cutting speeds, and adequate cooling are required. Annealing can eliminate processing stresses and restore ductility, with typical annealing temperatures for recrystallization ranging from 650 to 750°C.