DLC coating multiplies useable life of surgical instruments

According to the manufacturer, pure DLC coatings as thin a 2-3μm can increase the lifespan of a pair of Vannas scissors more than 100 times that of its uncoated counterpart. 

DLC is a revolutionary new coating that is being tested in a variety of industries. For example, when engine parts are coated, the DLC reduces friction and corrosion, increasing the life of the engine. In a completely different industry, DLC coating is being tested on metal heart valves. The coating is non-toxic, and it is so slick that biological material isn't likely to stick to it. Additionally, heart valves coated with pure DLC will last longer than their recipients, more than a hundred years.

What is it?

Natural diamonds are found in two different crystalline structures. The most common is a cubic lattice structure, and the rare form is a hexagonal lattice called lonsdaleite. DLC combines both forms of natural diamonds in a random pattern that gives a flexible, amorphous surface to the coating. While the surface of DLC is very smooth, under a microscope it looks like a cobblestone path. The random alterations of DLC between the cubic and hexagonal lattice structures of natural diamonds creates the unusual surface. DLC coating, in its pure form, is at least as hard as diamond and slicker than Teflon.

Seven different forms of DLC are available. The purest form is the most expensive, but it is also the hardest, slickest and strongest form. It is called tetrahedral amorphous carbon  (ta-C).

Properties of DLC

This amorphous, non-crystalline nature of DLC means it has no natural fracture planes, making DLC extremely strong. With positive reviews from the FDA, DLC coating is non-toxic and safe for biological applications. It is biologically compatible, chemically inert, optically transparent and resistant to wear.

Ideal coating for surgical instruments

While you can imagine a variety of uses from drill bits to artificial heart pumps, DLC coating is ideal for surgical instruments. The hardness of the coated surface resists wear and increases the life of the cutting edge. The anti-reflective coating resists glare, giving a better view of the surgical field. Additionally, DLC is corrosion-resistant. One of the hidden benefits is for patients. The reduced friction at the cutting site decreases necrosis of surrounding tissue and bone, promising a speedier recovery.