Vertebrae, the most advanced cable housing in the world

Limited Edition Vertebrae ZTA, ready to ship.

Feb 27, 2010 by Dr. Leslie Dean Brown
Vertebrae ZTA special editition We’re pleased to announce the launch of our latest model vertebrae cable housing, called “Vertebrae ZTA”. These are made of the ultimate ceramic material, zirconia toughened alumina (ZTA). ZTA is considerably stronger and tougher than our standard 96% alumina.
Due to the exhorbitant cost of this material, we have an extremely limited production run, enough for 6 brakesets and 6 gearsets. The ZTA editition is available in all the standard colours and will be on sale at the end of April 2010. If you would like to place an advance order, please contact us.

More about the ceramic toughening mechanism in ZTA:Transformation toughening is a breakthrough in achieving high-strength ceramic materials with very high fracture toughness. ZTA exhibits an internal mechanism for actually inhibiting crack propagation. A crack in a normal ceramic travels all the way through the ceramic with little inhibition, resulting in immediate and brittle fracture and catastrophic failure. Transformation Toughened Zirconia (TTZ) exhibits a fracture toughness (or resistance to crack propagation) which is 3-6 times higher than normal zirconia and most other ceramics. TTZ is so tough that it can be struck with a hammer or even fabricated into a hammer for driving nails. The stress intensity factor values for window glass (silica), transformation toughened alumina, and a typical iron/carbon steel range from 1 to 20 to 50 respectively.

Components manufactured from Zirconia Toughened Alumina (ZTA) show considerable improvement in strength and toughness over alpha alumina engineering ceramics. The increase in strength and toughness in ZTA is attributable to the stress induced transformation toughening mechanism which is introduced with the addition of optimized amounts of fine zirconia particles dispersed thoughout the alumina body.

zirconia transformation toughening in ceramics; a dispersed metastable tetragonal phase transforms into a monoclinic phase in the highly stressed zone around the crack tip, preventing further growth. It's not

Typical zirconia content is between 10% and 20%. As a crack grows through the ceramic, the crystal structure of the zirconia particles in the region of the crack changes from the metastable tetragonal phase to the stable monoclinic phase. The change increases the volume of the particles by about 3-4% and generates compressive stresses in the alumina matrix. This process closes the crack; although it does not ‘heal’ the damage, it does act as an energy barrier to further crack growth. The addition of zirconia to the alumina matrix increases fracture toughness by two times and can be improved by as high as four times, while compressive & flexural strength can be more than doubled.

7 Responses to “Limited Edition Vertebrae ZTA, ready to ship.”

  1. Dr. Leslie Brown Says:

    UPDATE: 1 set is already sold.
    Only 5 left on the entire planet!

  2. Dr. Leslie Brown Says:

    UPDATE: Our limited edition ZTA vertebrae has arrived one week early!!!

    Expect the “buy” page to be updated soon to reflect the availability of this special product…

  3. Dr. Leslie Brown Says:

    UPDATE: the second set of Vertebrae ZTA has now been sold. Only four remain.

  4. ken hillier Says:

    doc , put me on the list for a set of this flash zta stuff . if any sets left ! it will be used on a build of a custom habenero ti frame a replacement on warranty cos of a b/b crack near and thru left side weld .. go figure given that i smashed this frame over almost 5 years on the gold coast in queensland i am happy that mark hickey from habcycles agreed almost instantly to replace the frame ..and feel that the new one should reflect his committment to quality and ethics in design production and customer service .and also look good at the coffe shop … ..gonna chuck a saddle by ax lightness some b/b by zero ceramics and same ceramics inzipp 404s … with 7900 mechanical group any zta left … if not save some of the regular for me and advise by email .. i await your reply ..

  5. Dr. Leslie Brown Says:

    It’s all sold out now!

  6. Eduardo Zaeyen Says:

    Hi, I would like to by one for my 80Th Campy. Do you have plans to build more?

    Could you tel me more about Anubis housing?


    Eduardo Zaeyen

  7. Dr. Leslie Brown Says:

    If there is enough interest, we will build more… it probably won’t happen before mid 2014 though.

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