Mechanical Engineering / Makina Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4129
Browse
4 results
Search Results
Conference Object Open Cell Ti6al4v Foams for Biomedical Applications(Pamukkale Üniversitesi, 2006) Hızal, Alpay; Akar, Egemen; Güden, MustafaSintered Ti6Al4V alloy foams were prepared using atomized spherical powders in the porosity range of 52-72 % using a space holder. Powder-space holder mixture was cold compacted at 200, 300,400, 500 and 700 MPa compaction pressures and then sintered at 1200 C for 2 h and 1300 C for 2, 4 and 6 h. The porosity level and mean pore sizes of the sintered foams were determined as function of the compaction pressure and sintering temperature and duration. The compression strength and deformation behavior of the foams were investigated.Article Citation - WoS: 30Citation - Scopus: 33Processing and Compression Testing of Ti6al4v Foams for Biomedical Applications(Springer Verlag, 2009) Dizlek, Mustafa Eren; Güden, Mustafa; Türkan, Uğur; Taşdemirci, AlperOpen cell Ti6Al4V foams (60% porosity) were prepared at sintering temperatures between 1,200 and 1,350 °C using ammonium bicarbonate particles (315–500 μm) as space holder. The resulting cellular structure of the foams showed bimodal pore size distribution, comprising macropores (300–500 μm) and micropores (1–30 μm). Compression tests have shown that increasing sintering temperature increased the elastic modulus, yield and compressive strength, and failure strain of foams. The improvements in the mechanical properties of foams prepared using smaller size Ti64 powder with bimodal particle distribution were attributed to the increased number of sintering necks and contact areas between the particles. Finally, the strength of foams sintered at 1,350 °C was found to satisfy the strength requirement for cancellous bone replacement.Article Citation - WoS: 5Citation - Scopus: 5Foaming Behavior of Ti6al4v Particle-Added Aluminum Powder Compacts(Springer Verlag, 2009) Karsu, Nurettin Deniz; Yüksel, Sinan; Güden, MustafaThe foaming behavior of 5 wt.% Ti6Al4V (Ti64) particle (30–200 μm)-added Al powder compacts was investigated in order to assess the particle-addition effects on the foaming behavior. Al compacts without particle addition were also prepared with the same method and foamed. The expansions of Ti64 particle-added compacts were measured to be relatively low at small particle sizes and increased with increasing particle size. At highest particle size range (160–200 μm), particle-added compacts showed expansion behavior similar to that of Al compacts without particle addition, but with lower expansion values. Expansions studies on 30–45 μm size Ti64-added compacts with varying weight percentages showed that the expansion behavior of the compacts became very similar to that of Al compact when the particle content was lower than 2 wt.%. However, Ti64 addition reduced the extent of drainage. Ti64 particles and TiAl3 particles formed during foaming increased the apparent viscosity of the liquid foam and hence reduced the flow of liquid metal from cell walls to plateau borders. The reduced foamability in the compacts with the smaller size Ti64 addition was attributed to the relatively high viscosities, due to the higher cumulative surface area of the particles and higher rate of TiAl3 formation between liquid Al and Ti64 particles.Article Citation - WoS: 36Citation - Scopus: 45Cross Wedge Rolling of a Ti6al4v (eli) Alloy: the Experimental Studies and the Finite Element Simulation of the Deformation and Failure(Springer Verlag, 2012) Çakırcalı, Metin; Kılıçaslan, Cenk; Güden, Mustafa; Kıranlı, Engin; Shchukin, Valery Y.; Petronko, Vladimir V.The cross wedge rolling (CWR) deformation and fracture of a Ti6Al4Al (ELI) alloy were investigated experimentally and numerically using a coupled thermomechanical finite element model analysis. The experimentally determined flow stress and damage model parameters were verified by tension split Hopkinson pressure bar testing of notched samples. The simulation and experimental CWR forces showed well agreements except near the end of the stretching zone. The model analysis showed that the temperature distribution in the work piece was nonuniform during the CWR. When the initial temperature of the work piece was relatively low, the work piece temperature increased, a heating effect of the plastic deformation, while relatively high initial work piece temperatures resulted in cooling the work piece, caused by the work piece contact with the tools. The cracks were shown numerically to initiate in the midsections of the work piece during the guiding action and elongated in a direction normal to the maximum tensile stress triaxiality, resulting in cruciformshaped crack formation, which was well agreed with the previously observed crack shape.