Effect of SiC reinforcement particles on the grain density in a magnesium-based metal–matrix composite: Modelling and experiment

Abstract

Suchy, Jozef S.; Haberl, Katharina and Schumacher, Peter (2012). Effect of SiC reinforcement particles on the grain density in a magnesium-based metal-matrix composite: modelling and experiment. Acta Materialia, 60(6-7) pp. 2950-2958.For guidance on citations see FAQs. AbstractThe aim in this work is to develop a numerical model capable of predicting the grain density in the Mg-based matrix phase of an AZ91/SiC composite, as a function of the diameter and total mass fraction of the embedded SiC particles. Based on earlier work in a range of alloy systems, we assume an exponential relationship between the grain density and the maximum supercooling during solidification. Analysis of data from cast samples with different thicknesses, and mass fractions and particle diameters of added SiC, permits conclusions to be drawn on the role of SiC in increasing grain density. By fitting the data, an empirical nucleation law is derived that can be used in a micro-macro model. Numerical simulations based on the model can predict the grain density of magnesium alloys containing SiC particles, using the diameter and mass fraction of the particles as inputs. These predictions are compared with measured data.

Modeling of TiN and Ti2O3 Precipitates Formation During Solidification of Steel/ Modelowanie Powstawania Wydzieleń TiN I Ti2O3 W Procesie Krzepnięcia Stali

“…This means that the conditions for inclusion formation in the course of crystallization processes are favorable. The concentration C i0 of a given component "i" in the first part of the solidified phase is [17][18]: (18) where:…”

“…Time needed for a layer to solidify, i.e. local solidification time t s , depends on the cooling rate P (K/min) [17][18]:…”

“…After introducing finite differences in the place of difference increases, the following is obtained for the analyzed case [17][18][22][23]: A. For a cell at the dendrite (n=1)…”

“…The diffusion of component "i" in liquid phase takes place fast enough to make the concentration of the component constant in a given moment of time. The diffusion of component "i" in solid phase is described by the Fick law [17][18][19][20][21]:…”

Thermal Conductivity of Thin Walled Compacted Graphite Iron Castings

“…Customarily, this has led to the increased use of light alloys and composites. [1][2][3][4] From an economical and ecological point of view, thin walled castings made of ductile or compacted graphite cast iron can compete in terms of mechanical, foundry and thermophysical properties with light alloys and composites. [5][6][7] Compacted Graphite Iron (CGI) also known as Vermicular Graphite Iron is a modern engineering alloy with attractive features that enable its use in the automotive industry.…”