Titanium: Grade 1 vs. ASTM F136: What's the Difference?
When it comes to crafting hypoallergenic jewelry, titanium is a popular choice. But not all titanium is created equal. You might come across two common terms: Commercially Pure (CP) Grade 1 Titanium and ASTM F136 Titanium. I get asked sometimes what is the difference between these two types of titanium.
What is Commercially Pure Grade 1 Titanium?
Commercially Pure Grade 1 Titanium is one of the purest forms available, containing at least 99% titanium. It is classified as an "unalloyed" titanium, meaning it has no significant alloying elements added to it. The remaining 1% is made up of iron, carbon, nitrogen, and oxygen, which occur in tiny amounts.
Key Characteristics:
High Corrosion Resistance: Grade 1 titanium is highly resistant to corrosion from various elements, including seawater and chlorine, making it an excellent choice for jewelry that gets exposed to harsh environments.
Excellent Biocompatibility: Due to its purity, Grade 1 titanium is non-toxic and hypoallergenic, making it ideal for people with sensitive skin or metal allergies.
Malleability: This grade is the softest and most pliable of the commercially pure titanium grades, allowing for easier forming and shaping. This makes it perfect for creating intricate jewelry designs that require flexibility and precision.
Excellent weldability: Grade 1 titanium is highly weldable, making it possible to create strong connections.
Lightweight: Like all titanium, Grade 1 is incredibly light, providing comfort for daily wear without sacrificing durability.
What is ASTM F136 Titanium?
ASTM F136 Titanium is a designation for a specific type of titanium alloy known as Titanium 6Al-4V ELI (Extra Low Interstitial). This alloy comprises approximately 90% titanium, 6% aluminum, and 4% vanadium, with the "ELI" grade signifying lower levels of certain impurities, enhancing its mechanical properties.
Key Characteristics:
Superior Strength: The addition of aluminum and vanadium significantly increases the strength of ASTM F136 titanium compared to CP Grade 1. This makes it more durable and resistant to wear, which is particularly beneficial for jewelry that needs to withstand everyday use.
Excellent Biocompatibility: Due to its biocompatibility, ASTM F136 is a popular choice in medical implants, which means it is also a great choice for body jewelry. Like Grade 1, it is hypoallergenic and safe for prolonged skin contact. However, 6% of aluminum can cause an allergic reaction in people allergic to that metal.
Resistance to Deformation: The alloy's strength means it is less likely to deform or bend, maintaining its shape and integrity over time, even in thin, delicate jewelry pieces.
Brilliant Finish: ASTM F136 titanium can achieve a highly polished finish, adding to its appeal for high-end jewelry designs that require a luxurious look.
Key Differences:
Scope: ASTM F136 is a broader standard that encompasses multiple grades of unalloyed titanium, including Grade 1.
Requirements: Grade 1 titanium is a subset of ASTM F136, meaning it meets the standard's general requirements. However, ASTM F136 may have additional specific requirements for surgical implants that Grade 1 titanium might not fully meet in all cases.
Which One Should You Choose for Jewelry?
The choice between CP Grade 1 Titanium and ASTM F136 Titanium depends mainly on what you value most in your jewelry.
For those seeking comfort and hypoallergenic properties, especially if you prefer lightweight jewelry that is gentle on the skin, CP Grade 1 Titanium is an excellent choice. Its malleability makes it ideal for me to create custom, intricate designs while being durable and elegant.
At Nonita Jewelry, I prioritize the use of high-quality titanium in my creations. My pieces are crafted with care, ensuring that you receive jewelry that is not only beautiful but also safe and comfortable to wear.
