Choosing the Right Titanium Foil: A Guide to Grades and Manufacturing

When selecting titanium foil for your project, understanding the different grades is crucial. The choice directly impacts the foil’s strength, formability, and corrosion resistance. This guide will demystify titanium foil grades and provide a glimpse into how this incredible material is made.

Understanding Titanium Foil Grades: Commercially Pure (CP)

For foil applications, Commercially Pure (CP) grades are the most common. The primary difference is the allowable content of interstitial elements like oxygen and iron, which influences mechanical properties.

• Grade 1 (CP-4):

  • Key Property: Highest purity, lowest strength, and excellent ductility/formability.
  • Best For: Applications requiring complex forming or deep drawing, such as chemical processing vessel linings and architectural elements. It also offers the best corrosion resistance.

• Grade 2 (CP-3):

  • Key Property: The “workhorse” of CP titanium. It offers a perfect balance of moderate strength, excellent formability, and weldability.
  • Best For: A vast range of applications, including heat exchangers, aerospace components, and medical casings. It is the most widely used grade.

• Grade 4 (CP-1):

  • Key Property: The strongest of the CP grades. Its higher strength comes at the cost of reduced formability compared to Grades 1 and 2.
  • Best For: Applications where higher strength is needed without the complexity of an alloy, such as airframe components and cryogenic vessels.

Grade	Purity	Strength	Formability	Common Use Cases
Grade 1	Highest	Lowest	Excellent	Deep Drawing, Chemical Processing
Grade 2	High	Medium	Very Good	General Purpose, Heat Exchangers
Grade 4	Good	Highest (CP)	Fair	Airframe, High-Strength Parts

A Note on Alloy Grades

While less common in ultra-thin foil form, alloys like Grade 5 (Ti-6Al-4V) exist. This alloy offers significantly higher strength but is more challenging to form into a thin foil.

How Titanium Foil is Made: The Rolling Process

Creating something as thin and precise as titanium foil is a marvel of engineering. The primary manufacturing method is a multi-step rolling process:

1. Starting Material: The process begins with a cast titanium ingot.
2. Hot Rolling: The ingot is heated and passed through rollers to reduce its thickness into a slab.
3. Cold Rolling: The process switches to cold rolling (at room temperature) for a smoother finish and tighter tolerances.
4. Annealing: Between rolling passes, the foil is heat-treated in a vacuum to relieve internal stresses and restore ductility.
5. Final Pass: The final rolling pass achieves the target thickness and surface finish, often using specialized mills for exceptional precision.

Your Partner in Material Selection: Choosing the right grade of titanium foil is critical. Our team of experts is ready to help you navigate these options to find the perfect solution for your needs.