Effect of solidification rate on spatial distribution of SiC particles in A356 alloy composites

Kalkanlı, Ali
The damage and deformation behaviour of particulate reinforced metal matrix composites (PMMCs) can be highly sensitive to local variations in spatial distribution of reinforcement particles, which markedly depend on melt processing and solidification stages during production of PMMCs. The present paper attempts to study the effect of solidification rate on cluster formation in an Al-Si-Mg (A356) alloy composite reinforced with SiC particles and to explore the applicability of spatial functions to PMMC microstructures to quantify the degree of clustering The observed amount of clustering in composites was evaulated with the nearest neighbour and local density statistics in terms of variations in dendrite arm spacings and solid fractions at the dendrite coherencies. The results indicate that the distribution of SiC particles is controlled by the secondary dendrite arms. Depending on dendrite arm spacings and particle content, clustering is most pronounced at distance scales ranging approximately between 150 and 500 mu m, which is much larger as compared to the nearest neighbour distances.


Effect of cutting speed on tool performance in milling of B4Cp reinforced aluminum metal matrix composites
Karakas, M. Serdar; Acir, Adem; Ubeyli, Mustafa; Ögel, Bilgehan (Elsevier BV, 2006-09-14)
In this study, wear behavior of various tools in milling process of Al-4Cu/B4Cp composites was investigated. For this purpose, composite samples were produced by liquid phase sintering to be used in milling operation. Five different cutting speeds at a constant feed rate of 0.20 mm/z were used in order to determine the effect of cutting speed on tool wear and tool wear mechanism in milling of these composites. Milling operations were continued until flank wear limit (V-B)=0.3 mm was attained for each tool. ...
Control of the thickness distribution of evaporated functional electroceramic NTC thermistor thin films
Schmidt, R.; Parlak, Mehmet; Brinkman, Am (Elsevier BV, 2008-04-01)
In this work the thickness distribution of NTC thermistor thin films produced by low deposition rate (0.8 nm s(-1)) electron-beam evaporation is investigated. The target preparation, deposition conditions and geometrical set-up of the evaporation mechanism are described in detail. The evaporation geometry is shown to be critical for the thickness distribution of evaporated films. The film thickness distribution of evaporated layers was measured across a macroscopic film surface using Alpha Step stylus profi...
Numerical simulation of solidification kinetics in A356/SiCp composites for assessment of as-cast particle distribution
CETIN, Arda; Kalkanlı, Ali (Elsevier BV, 2009-06-01)
The present work is aimed at studying the effect of solidification rate on reinforcement clustering in particle reinforced metal matrix composites (PMMCs) through numerical simulations and experimental studies. A macrotransport-solidification kinetics (MTSK) model was used to simulate the solidification kinetics of the PMMCs. The experimental validation of the numerical model was achieved through the Newtonian and Fourier thermal analysis methods. Results reveal that the MTSK model can be successfully used ...
Generalized transient temperature behavior in induction heated workpieces
OKMAN, Oya; Dursunkaya, Zafer; Tekkaya, A. Erman (Elsevier BV, 2009-09-19)
Electromagnetic-thermal coupled numerical analysis of induction heating is time intensive if three-dimensional models are used. In this study, by processing the results of finite element computations, a dimensional analysis is carried out to predict the transient temperature rise time at the surface of an induction heated workpiece. A unique set of curves is found that describes the transient dimensionless temperature at a point on the surface as a function of the electromagnetic skin depth alone. The effec...
Effect of magnetic field and gamma irradiation on the electrical properties and structure of the Tl-based ceramic superconductors
Ozkan, H; Hasanlı, Nızamı; Kayed, T (IOP Publishing, 2000-02-01)
The voltage-current (V-I) characteristics, critical temperatures and the critical currents of Tl2Ba2CaCu2O8 (Tl-2212) and Tl2Ba2Ca2Cu3O10 (Tl-2223) ceramic superconductors were studied in magnetic fields up to 80 mT after several gamma irradiations up to 100 MR. The effect of gamma irradiation on the structure of these materials has also been studied. The normal state resistance increases by 20-30% with gamma irradiation, most of the changes taking place in low gamma doses up to 10 MR. The critical temperat...
Citation Formats
A. CETIN and A. Kalkanlı, “Effect of solidification rate on spatial distribution of SiC particles in A356 alloy composites,” JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, pp. 1–8, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47413.