Improving the performance of human hip implants by improving the processing quality and geometric accuracy of their spherical surfaces


  • Raul Turmanidze Georgian Technical University, Tbilisi
  • G. Popkhadze Georgian Technical University, Tbilisi
  • К. Inasharidze Shota Rustaveli State University, Batumi



single crystal sapphire, anisotropy, grindability, endoprosthesis, precision grinding, forming, spherical surface.


In view of the fact that the endo-prosthesis heads of human hip-joint are operated in extreme conditions, in respect of load, the selection of corresponding material and also increase of precision and quality of machining of spherical surfaces is rather topical task.

In the submitted work are reviewed the problems connected with definition of the influence degree of orientation of the sapphire crystal on its workability during diamond grinding with a butt of the ring and elaboration of the perspective, original scheme of formation of the incomplete spherical surface, particularly, of the sapphire head of endo-prosthesis of the human hip-joint.


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