Examination of Microstructure and Mechanical Properties of Powder Metal AA 2014-SiC-B4C Composite / Hybrid Materials

In this study, the production, microstructure and mechanical properties of AA 2014 aluminum alloy and B4C-SiC ceramic particle reinforced hybrid metal matrix composite materials were investigated by powder metallurgy. For this purpose, SiC (5-10-15%), B4C (5-10-15%) and B4C-SiC (10%-10%) ceramic particle reinforced composite and hybrid composite materials were produced in different volume ratio on aluminum matrix structure. Matrix and reinforcement powder blends were sintered under argon atmosphere at 600ºC for 1 hour by pressing one-way as block-shaped samples under 700MPa. The produced experiment specimens were characterized in terms of SEM (Scanning Electron Microscope), Optical microscope and micro hardness (HV 0. 1) measurements. It was shown that aluminium matrix structure exhibited homogenous distribution depending on the increase in the volume ratio of B4C ve SiC ceramic particles; this was detected with microstructure images. According to the AA 2014 aluminum alloy, the hardness values were found to increase due to the increasing SiC and B4C ceramic particle reinforcement ratio. In B4C-SiC particle reinforced hybrid composite materials, the micro hardness value was relatively reduced compared to the single ceramic phase reinforcement containing B4C 15% ve %15 SiC

Effect of Impactor Mass on Dynamic Response and Retention Properties of Composite Plates under Successive Impacts

This study mainly focuses on the effect of mass of impactor upon dynamic response of laminated composites. For this purpose two different impactors with different masses were used. The impact velocities were selected so that impactors with different masses had the same kinetic energy. The experiments were performed on simply supported woven E-glass reinforced epoxy laminates which are made of 8 layers stacked symmetrically. The variation of impact force, impactor velocity and laminate displacement versus interaction time were obtained. The impulse and energy absorption characteristics and damage zones were also investigated. After low velocity impact, the test specimens were subjected to three-point bending testing in order to get retention mechanical properties

Production and mechanical characterization of prismatic shape machine element by recycling of bronze and cast-iron chips

Bu çalışmada küresel grafitli dökme demir (GGG-40) ve Bronz (CuSn10) talaşlarının izostatik sıcakpresleme yöntemiyle geri dönüştürülmesi ile üretilen metal matrisli kompozit malzemelerin (MMK) üretimive mekanik davranışları incelenmiştir. MMK malzemeler 4 farklı karışım oranında 3 farklı sıcaklıkta ve 3farklı basınçta üretilerek üretim parametrelerinin gözeneklilik, sertlik ve eğilme mukavemeti üzerine etkisiincelenmiştir. Prizmatik geometrili olarak üretilen numunelerin öncelikle gözeneklilik ve yoğunluk değerleritespit edilmiştir. Daha sonra Brinell ve Mikro Vickers ve 3 noktadan eğilme deneyleri ile MMKmalzemelerin mukavemeti belirlenmiştir. Optik mikroskopi tekniği ile mikro yapı görüntüleri incelenerektalaşların birleşme mekanizması incelenmiştir. Ayrıca XRD analizi aracılığıyla metalik talaşlar arasında arafaz oluşumu olup olmadığı sorgulanmıştır. Gözeneklilik deneyleri neticesinde %20 mertebelerindegözeneklilik elde edilmiştir. Aşırı plastik deformasyon gösteren CuSn10 sebebiyle mukavemeti artanCuSn10 talaşları sertlik değerini Bulk CuSn10 ile kıyaslanabilir seviyelere getirmiştir. Eğilme deneyineticesinde MMK malzemelerin eğilme mukavemetleri bulk CuSn10’dan düşük çıkmıştır. Sonuç olarakmetal talaşların başarılı bir biçimde metal matris kompozit haline getirilebileceği gösterilmiştir.In this study, the production and mechanical properties of porous metal matrix composites (MMC’s) byrecycling of spheroid cast iron chips (GGG-40) and bronze chips (CuSn10) by hot isostatic pressing wasinvestigated. The metal matrix composites were produced with four different CuSn10 contents, threedifferent pressures and temperatures and effects of production parameters on porosity, hardness, flexureproperties were examined. Samples were produced in prismatic shape with specified porosity. Themechanical properties were determined by Brinell and Micro Vickers hardness tests and three-point bendingtest. The consolidation mechanism of metallic chips was also investigated with optic microscopy. It wasexamined whether any second phase occurred between metallic chips by the help of XRD test. As a result ofporosity test, it is found that metal matrix composites can have porosity value of as much as 20%. It is alsoshowed that owing to excessive plastic deformation of CuSn10, the hardness of MMC material can be higherthan bulk CuSn10. Three-point bending test showed that the flexure properties of MMC materials are islower than that of bulk CuSn10. As a consequence, it showed that metallic chips were recycled with hotpressing successfully