Szlancsik A.,Muegyetem rakpart |
Katona B.,Muegyetem rakpart |
Majlinger K.,Muegyetem rakpart |
Orbulov I.N.,Muegyetem rakpart |
Orbulov I.N.,Budapest University of Technology and Economics
Materials | Year: 2015
Iron hollow sphere filled aluminum matrix syntactic foams (AMSFs) were produced by low pressure, inert gas assisted infiltration. The microstructure of the produced AMSFs was investigated by light and electron microscopy, extended by energy dispersive X-ray spectroscopy and electron back-scattered diffraction. The investigations revealed almost perfect infiltration and a slight gradient in the grain size of the matrix. A very thin interface layer that ensures good bonding between the hollow spheres and the matrix was also observed. Compression tests were performed on cylindrical specimens to explore the characteristic mechanical properties of the AMSFs. Compared to other (conventional) metallic foams, the investigated AMSFs proved to have outstanding mechanical properties (yield strength, plateau strength, etc.) and energy absorbing capability. © 2015 by the authors.
Dobranszky J.,Budapest University of Technology and Economics |
Ring G.,Muegyetem rakpart |
Bognar E.,Muegyetem rakpart |
Kovacs R.,Budapest University of Technology and Economics |
Bitay E.,Transylvania University
Acta Polytechnica Hungarica | Year: 2014
In invasive radiology, X-ray imaging is used in both tracking the delivery system and assisting in correct positioning of stents. Until now there has been no objective and quantitative scale of X-ray visibility which is also known as radiopacity. There is a clear need from the part of interventional cardiologists for a quantitative in vitro evaluation method with which X-ray visibility can be graded repeatably, objectively, in a validated form across a wide range of fields. Therefore the development of the presented quantitative evaluation approach was decided in order to unambiguously classify the radiopacity of given cardiovascular implants under given in vitro imaging conditions. In this work the relative X-ray visibility index (XVR), which expresses the visibility of the stent compared to the background and the method for determining the value of this index, is introduced. The XVR index is related to a simple quantification method based on image analysis of X-ray images of stents. Nevertheless, this stent radiopacity quantification method can also be used in a wide range of clinical contexts.