Computer-Integrated Safe Design of FGM Component for Hip Replacement Prosthesis

Abstract

Computer-integrated safe design of FGM component for hip replacement prosthesis was presented based on principle of optimal stresses distribution in the FGM component. The goals were to create an FGM structure with reasonable compressive stresses on the surfaces (subjected to wear) and to keep them during the entire manufacturing cycle (sintering, machining, assembling and application). The residual stresses developed in the different parts of the composite were implemented into the subsequent process of the surface grinding and assembly to simulate properly the whole processing route to ensure optimal combination of the processing parameters.

The effect of residual stresses in functionally graded alumina–ZTA composites on their wear and friction behaviour

“…The result is a stress gradient with residual tensile stresses in the zirconia-containing core and compressive stresses in the outer alumina layer. 9 The stress profiles determined for the sintered and HIP-ed samples prepared in the present investigation, i.e., for the step-graded discs with three (sample AZ-1) or seven layers (sample AZ-2), are presented in Fig. 1a and b, respectively.…”

Mode-3 spontaneous crack propagation along functionally graded bimaterial interfaces

“…Functionally graded materials used in thermal barrier coatings were manufactured by combining ceramics and metals so as to achieve high toughness at high temperatures. Current applications of functionally graded materials include wear resistant coatings (Schulz et al, 2003;Gasik et al, 2003;Put et al, 2003;Melgarejo et al, 2006), manufacture of microelectromechanical systems MEMS (Witvrouw and Mehta, 2005), sensors (Muller et al, 2003) and biological implants (Pompe et al, 2003;Watari et al, 2004;Zhang et al, 2005). Graded materials have also found applications in electronic components (Wosko et al, 2005;Kato et al, 2006).…”

Modelling of Processing of FGM Bioimplants

“…Biomaterials are being used to replace and repair human tissues and bones [1][2][3][4]. One of the important applications of biomaterials is in prostheses manufacturing, of which hip and knee prostheses are possibly the most widely used.…”

“…Existing solutions of materials combinations are not very satisfactory due resulting to wear debris causing complications and low level of mechanical properties in the case of ceramics. In order to provide superior mechanical, good wear resistance and biological properties in vivo, the functionally graded materials concept can be introduced in to the hip joints design [4].…”

“…Composites of alumina and zirconia were studied as an FGM structure having compressive stresses on the wear surfaces during the entire processing cycle (sintering, machining, assembling and application) [4,5]. It is known that residual thermal stresses developed in the different parts of the component will affect its lifetime.…”