Mechanical Engineering / Makina Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4129
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Conference Object Quasi-Static Axial Crushing Behavior of Aluminum Closed Cell Foam-Filled Multi-Packed Aluminum and Composite/Aluminum Hybrid Tubes(The European Association for Experimental Mechanics, 2007) Güden, Mustafa; Kavi, Halit; Yüksel, Sinan; Taşdemirci, AlperThe axial crushing behavior of empty and Al close-cell foam-filled Al multi-tube designs (hexagonal and square) and E-glass woven fabric polyester composite and Al hybrid tubes were investigated through quasi-static compression testing. The effects of foam filling on the deformation mode and the crushing and average crushing loads of single tubes and multi-tube designs were determined. Although foam filling increased the energy absorption in single Al tube and multi-tube designs, it was not effective in increasing the specific absorbed energy over that of the empty Al tube. However, multi-tube designs were found to be energetically more effective than single tubes at similar foam filler densities, proving a higher interaction effect in multi-tube designs. Empty composite and empty hybrid tubes crushed predominantly in progressive crushing mode, without applying any triggering mechanism. Foam filling was found to be ineffective in increasing the crushing loads of the composite tubes over the sum of the crushing loads of empty composite tube and foam. However, foam filling stabilized the composite progressive crushing mode. In empty hybrid tubes, the deformation mode of the inner Al tube was found to be a more complex form of the diamond mode of deformation of empty Al tube, leading to higher crushing load values than the sum of the crushing load values of empty composite tube and empty metal tube.Conference Object High Strain Rate Reloading Compresson Testing of a Closed-Cell Alumnum Foam(The European Association for Experimental Mechanics, 2007) Taşdemirci, Alper; Güden, Mustafa; Hall, Ian W.Aluminum (Al) closed-cell foams are materials of increasing importance because they have good energy absorption capabilities combined with good thermal and acoustic properties. They can convert much of the impact energy into plastic energy and absorb more energy than bulk metals at relatively low stresses. When used as filling materials in tubes, they increase total energy absorption over the sum of the energy absorbed by foam alone and tube alone [1]. In designing with metallic foams as energy absorbing fillers, mechanical properties are needed for strain rates corresponding to those created by impact events. Quasi-static mechanical behavior of metallic foams has been fairly extensively studied, but data concerning high strain rate mechanical behavior of these materials are, however, rather sparse [2,3]. This study was initiated, therefore, to study and model the high strain rate mechanical behavior of an Al foam produced by foaming of powder compacts and to compare it with quasi-static behavior and, hence, determine any effect on energy absorbing capacity.Conference Object Alüminyum Köpük Dolu Kompozit/alüminyum İkili Tüplerin Ezilme Davranışları(Pamukkale Üniversitesi, 2006) Yüksel, Sinan; Tanoğlu, Metin; Güden, MustafaTüp sarma yöntemiyle hazırlanan ince duyarlı cam fiber takviyeli polyester kompozit/Alüminyum ikili tüplerin ezilme davranışları statik basma hızlarında (25 mm/dak) deneysel incelenmiştir. Tüplerde dolgu malzemesi olarak kullanılan Al köpüğün ezilme yük değerlerine ve deformasyon mekanizmalarına etkileri belirlenmiştir.Conference Object Kompozit Alüminyum Köpüklerin Hazırlanması ve Mekanik Özelliklerinin Belirlenmesi(2015) Güden, Mustafa; Elbir, Semih; Yılmaz, SelahattinPreslenmiş tabletlerin ısıtılması yöntemi ile hazırlanan kapalı hücreli SiC-parçacık takviyeli alüminyum kompozit köpüğün köpükleşme ve basma mekanik testi özellikleri belirlenmeye çalışılmıştır. Bu özellikler aynı yöntemle hazırlanan saf alüminyum köpüğün özellikleri ile karşılaştırılmıştır. Sonuçlar, SiC-parçacık takviyeli köpüklerde köpükleşmenin ve plato gerilmesinin daha yüksek olduğunu göstermiştir.Conference Object Axial Compression of Aluminum Closed-Cell Foam Filled and Empty Aluminum Tubes(Uludağ Üniversitesi, 2002) Toksoy, Ahmet Kaan; Güden, Mustafa; Hall, Ian W.Aluminum closed-cell foam filled aluminum tubes with a polyester bonding layer between foam core and tube wall have been compression tested in ord er to detemiine specific energy absorption for the crash box applications. Aluminum foam, empty and foam filled tubes without bonding layer were also tested for comparison purposes, Preliminary results have shown that interaction effect has been found in foam filled tubes with polyester layer. In order to identify deforiDation mechanisms involving with tube deforination, deformed empty and foam filled tubes crosssections were microscopically analyzed and operative defoimationmechanisms were determined.Conference Object Alüminyum Köpük Dolu Alüminyum Tüplerin Ezilme Davranışları(Pamukkale Üniversitesi, 2004) Kavi, Halit; Yüksel, Sinan; Tanoğlu, Metin; Güden, MustafaSon yıllarda hafif alüminyum köpük dolu tüplerin çarpışma enerjisi sönümleme amaçlı kullanımı için artan bir ilgi vardır. Tekli veya iç içe geçmiş köpük dolu tüpler bu amaç doğrultusundaki bu uygulamalar için çalışılmasına rağmen altıgen ve kübik paketleme geometrileri henüz araştırılmamıştır. Bu çalışmanın nihai amacı tekli köpük dolu tüplerin enerji emme kapasitesini artıracak çoklu tüp geometrilerini belirlemektir. Dolgu malzemesi olarak kullanılan alüminyum köpük malzemeler toz metalürjisi yöntemi ile hazırlanmıştır. Köpük numuneler blok köpük malzemeden kesilerek hazırlanmıştır. Alüminyum köpük dolu tekli tüpler üzerinde basma testleri yapılmış ve sonuçlar ortalama ezilme kuvveti cinsinden değerlendirilmiştir.Conference Object Alüminyum Kapalı Hücreli Köpüklerin Toz Metalürjisi Yönetimi ile Üretilmesi(Pamukkale Üniversitesi, 2004) Güden, Mustafa; Kavi, Halit; Toksoy, Ahmet KaanSon şekle yakın Alüminyum kapalı hücreli yapılar, örneğin otomobil tampon ve kapıları, tabletlerin köpükleştirilmesi metodu olarak bilinen toz metalürjisi yöntemi ile hazırlanmaktadır. Metot tozların karıştırılması, sıcak preslenmesi ve elde edilen toz tabletlerin kullanılan alaşımın ergime sıcaklığının üstüne ısıtılması suretiyle köpükleştirilmesi süreçlerinden oluşmaktadır. Bu çalışmada, toz metalürjisi metodu ile kapalı hücreli alüminyum köpük metal üretim parametreleri ve üretim sonucu ortaya çıkan mikroyapılar, köpüğün yoğunluğuna bağlı mekanik özellikleri ile birlikte özetlenmektedir. Son olarak, alüminyum köpük metalin yuvarlak tüplerde dolgu malzemesi olarak kullanımına yönelik deneysel çalışmaların sonuçları otomobil ezilme kutularında kullanımına yönelik örnek olarak verilmiştir.Article Citation - WoS: 54Citation - Scopus: 62Sic-Particulate Aluminum Composite Foams Produced by Powder Compacts: Foaming and Compression Behavior(Springer Verlag, 2003) Elbir, Semih; Yılmaz, Selahattin; Toksoy, Ahmet Kaan; Güden, Mustafa; Hall, Ian W.The foaming behavior of SiC-particulate (8.6% by volume) aluminum composite powder compacts contained Titanium Hydride blowing agent was investigated by heating above the melting temperature (750°C) in a pre-heated furnace. Aluminum powder compacts were also prepared and foamed using similar compaction and foaming parameters in order to determine the effect of SiC-particulate addition on foaming and compression behavior. The linear expansions of the compacts at various furnace holding times were ex situ determined. Optical and scanning electron microscopy techniques were used to characterize prepared and deformed foams microstructures. The SiC-particulate addition was found to increase the linear expansion and reduce the extent of the liquid metal drainage and cell coarsening of the aluminum compacts. The composite foam samples also showed higher compressive stresses, but a more brittle behavior as compared with aluminum foams.Article Citation - WoS: 55Citation - Scopus: 61Sic-Particulate Aluminum Composite Foams Produced From Powder Compacts: Foaming and Compression Behavior(Springer Verlag, 2006) Güden, Mustafa; Yüksel, SinanThe foaming behavior of SiC-particulate (SiCp) aluminum composite powder compacts containing titanium hydride blowing agent was investigated by heating to 750°C in a pre-heated furnace. Aluminum powder compacts were also prepared and foamed using similar compaction and foaming parameters in order to determine the effect of SiCp-addition on the foaming and compression behavior. The SiCp-addition (10 wt%) was found to increase the linear expansion of the Al powder compacts presumably by increasing the surface as well as the bulk viscosities. The compression tests conducted on Al and 10 and 20% SiCp foams further showed a more brittle compression behavior of SiCp/Al foams as compared with Al foams. The collapse stresses of Al and 10% SiCp/Al foams were also predicted using the equations developed for the open and closed cell foams. Predictions have shown that Al foam samples behaved similar to open cell foams, while 10% SiCp/Al foam collapse stress values were found between those of open and closed cell foams, biasing towards those of the open cell foams.Article Citation - WoS: 4Citation - Scopus: 5Improving the Energy Absorption of Closed Cell Aluminum Foams(Chapman & Hall, 2002) Greene, S. A.; Hall, Ian W.; Güden, MustafaClosed cell aluminum foams have received much recent attention as energy absorbing materials on account of their ability to undergo extensive deformation at a relatively low stress called the plateau stress. Several studies describe the improvements in energy absorption to be obtained, relative to their empty counterparts, when foam filled tubes are crushed either quasi-statically or dynamically [1–4]. Al foams are also of possible interest for ballistic applications because they present a very large acoustic impedance mismatch with common armor materials, offering the possibility of being able to modify theway in which elasticwaves travel through multi-component armor.