Grade Designation and Composition
TA1 is a Chinese designation for commercially pure titanium with the lowest interstitial content in the TA series. It corresponds closely to ASTM Grade 1, UNS R50250. The material is essentially unalloyed titanium, with tight limits on the interstitial elements oxygen, nitrogen, carbon and hydrogen, because these elements control both strength and ductility.
Iron is present only as a residual impurity. The low oxygen content, typically capped around 0.18 percent, is the main reason TA1 has lower strength but higher ductility than TA2 and TA3.
Mechanical Properties
In the annealed condition TA1 delivers a minimum tensile strength of about 240 MPa and a minimum yield strength of about 170 MPa, with elongation typically above 24 percent depending on product form. Hardness is low, which makes the material easy to machine, cold form and weld.
The low strength is offset by exceptional ductility and toughness. TA1 can be deeply drawn, spun and bent to tight radii without cracking, and it retains good toughness at cryogenic temperatures.
Corrosion Resistance and Weldability
TA1 forms a stable, self-healing oxide film that protects the metal in seawater, chlorides, oxidising acids and most natural environments. Because it contains no alloying elements, there is no risk of selective phase corrosion, and the material is immune to chloride stress corrosion cracking.
Welding is straightforward with proper inert gas shielding. The weld zone recovers ductility after welding, and the corrosion resistance of the welded joint matches the parent metal in most media.
Typical Applications
TA1 is used for chemical equipment linings, heat exchanger components, evaporator bodies, seawater piping, food processing equipment and architectural cladding. Its formability makes it the preferred grade for deep-drawn components, bellows, expansion joints and anode baskets used in electroplating.
The material also appears in medical and pharmaceutical equipment where purity and corrosion resistance are important, and in desalination plants where long-term seawater resistance is required.
Supply Forms and Standards
TA1 is supplied as plate, sheet, strip, bar, rod, wire, tube and forging stock. In the international system the equivalent material is ordered to ASTM B265 for sheet and strip, ASTM B348 for bar and billet, and ASTM B338 or B861 for tube, all under Grade 1 with UNS R50250.
Mechanical properties, chemistry and dimensional tolerances are verified against the applicable specification before release, and the material can be supplied in annealed or cold-worked tempers.
Frequently Asked Questions
Q: What is TA1 titanium?
A: TA1 is a commercially pure titanium grade with the lowest interstitial content and strength in the TA series, corresponding to ASTM Grade 1 with UNS designation R50250.
Q: What is the tensile strength of TA1?
A: In the annealed condition the minimum tensile strength is about 240 MPa, with a minimum yield strength of about 170 MPa and high elongation.
Q: Why choose TA1 instead of TA2 or TA3?
A: TA1 offers the best formability, weldability and ductility, and it is chosen when deep drawing, tight bending or maximum corrosion resistance matters more than strength.
Q: Is TA1 corrosion resistant in seawater?
A: Yes, TA1 is highly resistant to seawater and chloride environments, and it is immune to chloride stress corrosion cracking.
Q: How is TA1 supplied?
A: TA1 is supplied as plate, sheet, strip, bar, rod, wire, tube and forging stock, normally in the annealed condition.
