Mechanical Engineering / Makina Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4129
Browse
2 results
Search Results
Article Citation - WoS: 37Citation - Scopus: 42Effects of Compaction Pressure and Particle Shape on the Porosity and Compression Mechanical Properties of Sintered Ti6al4v Powder Compacts for Hard Tissue Implantation(John Wiley and Sons Inc., 2007) Güden, Mustafa; Çelik, Emrah; Hızal, Alpay; Altındiş, Mustafa; Çetiner, SinanSintered Ti6Al4V powder compacts potentially to be used in implant applications were prepared using commercially available spherical and angular powders (100-200 mum) within the porosity range of 34-54%. Cylindrical green powder compacts were cold compacted at various pressures and then sintered at 1200 degrees C for 2 h. The final percent porosity and mean pore sizes were determined as functions of the applied compaction pressure and powder type. The mechanical properties were investigated through compression testing. Results have shown that yield strength of the powder compacts of 40-42% porosity was comparable with that of human cortical bone. As compared with previously investigated Ti powder compacts, Ti6Al4V powder compacts showed higher strength at similar porosity range. Microscopic observations on the failed compact samples revealed that failure occurred primarily by the separation of interparticle bond regions in the planes 45 degrees to the loading axis. Effects of compaction pressure and particle shape on the porosity and compression mechanical properties of sintered Ti6Al4V powder compacts for hard tissue implantation.Article Citation - WoS: 41Citation - Scopus: 49Compression Testing of a Sintered Ti6al4v Powder Compact for Biomedical Applications(Elsevier Ltd., 2005) Güden, Mustafa; Çelik, Emrah; Akar, Egemen; Çetiner, SinanIn this study, the compression deformation behavior of a Ti6Al4V powder compact, prepared by the sintering of cold compacted atomized spherical particles (100–200 Am) and containing 36–38% porosity, was investigated at quasi-static (1.6 10 3–1.6 10 1 s 1) and high strain rates (300 and 900 s 1) using, respectively, conventional mechanical testing and Split Hopkinson Pressure Bar techniques. Microscopic studies of as-received powder and sintered powder compact showed that sintering at high temperature (1200 8C) and subsequent slow rate of cooling in the furnace changed the microstructure of powder from the acicular alpha (a) to the Widmanst7tten (a+h) microstructure. In compression testing, at both quasi-static and high strain rates, the compact failed via shear bands formed along the diagonal axis, 458 to the loading direction. Increasing the strain rate was found to increase both the flow stress and compressive strength of the compact but it did not affect the critical strain for shear localization. Microscopic analyses of failed samples and deformed but not failed samples of the compact further showed that fracture occurred in a ductile (dimpled) mode consisting of void initiation and growth in a phase and/or at the a/h interface and macrocracking by void coalescence in the interparticle bond region.