Selection Guide | How to Choose Between TA1 and TA2 Titanium Foil?

Both TA1 (Gr1) and TA2 (Gr2) are classified as "titanium foil" and are the most common grades on the market. Procurement teams often struggle to distinguish between them, which can lead to issues during production—such as corrosion, cracking during stamping, or poor surface quality. This guide clarifies the selection logic once and for all.

First, let’s look at the core differences: Both are commercially pure titanium with a titanium content exceeding 99.2%. They differ primarily in their oxygen content, strength, and plasticity.

✅ TA1 (Gr1): Features lower oxygen content, superior plasticity, greater softness, better corrosion resistance, and stable electrical conductivity. It is ideal for applications requiring complex stamping (such as flow channels), fuel cell bipolar plates, electrolytic electrodes, and precision-etched components. Choose TA1 if the material will undergo subsequent bending or deep drawing. Its drawback is lower strength, making it unsuitable for structural components that require high rigidity. Gr2 Pure Titanium Foil 

✅ TA2 (Gr2): Contains slightly more oxygen, resulting in higher strength, better wear resistance, and greater resistance to deformation, though its corrosion resistance is marginally lower than that of TA1. It is well-suited for applications that do not involve complex stamping but require load-bearing capacity and wear resistance—such as anti-corrosion linings for chemical equipment, thermal shielding, standard gaskets, and non-formed medical substrates. It is the most widely circulated, general-purpose grade of titanium foil on the market.

Beyond the grade, several other parameters are more critical than thickness alone when sourcing titanium foil: Gr1 Pure Titanium Foil

1. **Thickness Tolerance**: High-end titanium foil for new energy applications requires tolerances as tight as ±0.001 mm. Larger tolerances can lead to inconsistent flow channels in bipolar plates or fluctuations in internal battery resistance. For standard anti-corrosion gaskets, these tolerances can be more relaxed.

2. **Surface Condition**: Options include pickled surfaces or bright-rolled (shiny) surfaces. A bright (polished) finish is suitable for etching, sputtering, and coating; a pickled finish is more cost-effective and well-suited for anti-corrosion linings. The surface must be free from scratches, peeling, oxidation discoloration, or oil stains.

3. **Sheet Shape and Flatness**: Ultra-thin titanium foil is highly prone to waviness and warping. Poor tension control during coiling can lead to the material being rendered unusable during subsequent die-cutting or stamping processes.

4. **Compatibility with Downstream Processes**: If surface coating is required (e.g., carbon coating for fuel cell bipolar plates), there are strict requirements for substrate roughness and cleanliness; the target surface roughness (Ra value) must be agreed upon with the material manufacturer in advance.

5. **Width**: Wider titanium foil reduces the need for welded seams, making it ideal for continuous automated production lines; however, it is more difficult to roll and comes at a higher cost.

Common Pitfalls to Avoid:

❌ Misconception 1: Thicker is better. Titanium foil is expensive, so choosing an unnecessarily thick gauge only drives up costs. For fuel cell bipolar plates, a thickness of 0.1–0.15 mm is the industry standard and is sufficient for the application.

❌ Misconception 2: Using stainless steel foil instead of titanium to save money. While stainless steel may appear cheaper in the short term, it may have only one-third the service life of titanium foil in environments containing chlorine or acidic electrolytes, resulting in a higher total lifecycle cost.

❌ Misconception 3: Focusing solely on thickness while ignoring the material grade. Using TA2 (Grade 2 titanium) for deep-drawn bipolar plates carries a high risk of cracking during the stamping process.

A Quick Guide to Selection: Choose **TA1** for applications involving stamping, exposure to highly corrosive environments, or use as an electrode. Choose **TA2** when higher strength is required, or for use in gaskets, anti-corrosion shielding, or linings. Before making a purchase, provide the supplier with details regarding the operating medium, temperature, forming method, and whether any coating will be applied—this ensures you receive the titanium foil specification best suited to your needs.