| Cementless fixation of orthopaedic implants through bone ingrowth allows long-term implant anchorage in bone. Sintering of metallic particles onto the substrate of an orthopaedic implant results in a porous surface structure with a 3-dimensional interconnected pore geometry into which bone tissue can attach. Shedding of sinter-bonded particles from the substrate due to loading of the implant can result in unacceptable third-body wear and loosening of the implant. This study examined the shear strength of the particle/substrate interface for specimens sintered at different temperatures. Fatigue properties of sintered porous coated Ti-6Al-4V ELI rotating beam fatigue specimens and notched, as-sintered Ti-6Al-4V ELI axial fatigue specimens were studied as a function of sintering temperature to ensure that increased sintering temperature did not adversely affect the fatigue endurance strength.;The alloy studied was Ti-6Al-4V ELI. The particles used were atomized spherical particles approximately 150mum to 250mum in diameter (-60/+80 mesh). Sintering, and heat treatment to simulate sintering, was done at 1250°C, 1275°C, 1300°C, and 1315°C in a vacuum (<10 -5 Torr) furnace. (Abstract shortened by UMI.)... |
