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What is Oxygen Free Copper?


C101 Oxygen Free Copper is extremely pure copper with very little oxygen content. With a typical oxygen content of less than 0.0005% and a typical copper grade of 99.99%, C101 Oxygen Free Copper is the highest-grade copper available, and the material properties closely resemble that of elemental copper. The target purity is so high that silver is removed as an impurity.

As an ultra-high purity copper product, C101 Oxygen Free Copper has very good electrical and thermal conductivity, has good machinability, and is highly ductile. By reducing the oxygen content to less than 0.0005% these properties are more exaggerated than standard copper products and as such find a variety of highly specialized industrial applications.

What is Oxygen Free Copper used for?

The higher the purity of any copper product, the better the corrosion resistance, the higher the electrical conductivity, and less heat is produced while conducting electricity. As the purest copper product possible, C101 Oxygen Free Copper provides the best results of any copper products.

By removing almost all impurities there are very few interruptions to the metallic structure of the copper, and by removing almost all oxygen there is a significant reduction in oxidation of the metallic copper which can further impede performance.

Due to the higher price that comes with the higher purity product, almost all uses of C101 Oxygen Free Copper are highly specialized. These include:

  • Superior Audio/Visual Applications – high end audio/visual applications where quality is paramount will utilize copper wiring made from C101 Oxygen free Copper.
  • Large industrial transformers – the increased electrical conductivity of C101 Oxygen Free Copper can reduce the diameter of the wiring within transformers and therefore reduce the amount of copper and the size of the overall installation.
  • Long life applications – In large or very difficult to replace projects, the longer lifespan of C101 Oxygen Free Copper products can be beneficial.
  • High vacuum applications – Any scientific requirement to minimize the presence of impurities in a vacuum environment can utilize C101 Oxygen Free Copper to ensure no contamination happens from the copper wiring.

Often more than one of the above applications are found in an installation of C101 Oxygen Free Copper, such as in the largest particle accelerator in the world, the Large Hadron Collider.

How is Oxygen Free Copper made?

The processing of C101 Oxygen Free Copper only differs in the final refining stage. Where standard high purity copper is refined using standard atmospheric conditions, to reduce the oxygen content further. The final refining process must be conducted in an oxygen free environment.

This can include smelting and pouring molten copper into casts in an oxygen free environment, such as a vacuum or a carefully controlled inert atmosphere. Due to the extra processing complexity to generate the required product purity, C101 Oxygen Free Copper is the most expensive copper grade on the market.

Looking for copper for your next project? Metal Supermarkets offers a variety of copper shapes, cut to the size you need. Shop now

Metal Supermarkets

Metal Supermarkets is the world’s largest small-quantity metal supplier with over 125 brick-and-mortar stores across the US, Canada, and United Kingdom. We are metal experts and have been providing quality customer service and products since 1985.

At Metal Supermarkets, we supply a wide range of metals for a variety of applications. Our stock includes: mild steel, stainless steel, aluminum, tool steel, alloy steel, brass, bronze and copper.

We stock a wide range of shapes including: bars, tubes, sheets, plates and more. And we can cut metal to your exact specifications.

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