A micro-model for aluminum-silicon alloys

Journal Article · Tue Oct 01 00:00:00 EDT 1996 · Scripta Materialia

DOI:https://doi.org/10.1016/1359-6462(96)00232-1· OSTI ID:382488

Vijayaraghavan, R; Bradley, F ^[1]; Palle, N; Boileau, J; Zindel, J; Beals, R ^[2]

---

1. Univ. of Wisconsin, Madison, WI (United States)
2. Ford Motor Co., Dearborn, MI (United States)

A356 and A319 are aluminum-silicon casting alloys used in automobile powertrain castings such as engine blocks and cylinder heads. It is of interest to model solidification and microstructure evolution in these alloys as a function of melt composition and processing conditions. There are essentially two approaches to solidification modeling. The first is that of macro-modeling where heat flow is considered on a large scale with the intent of verifying gating system design and estimating overall solidification times for different regions of the casting. The second approach is a more fundamental approach that uses micro-models to estimate latent heat and fraction of solid evolution. The micro-models estimate the evolution of fraction of solid during solidification using nucleation and growth kinetics. These kinetics can be evaluated using first principles which is usually computationally very intensive, or they can be evaluated using experiments. This work describes an implementation of one such micromodel for Al-Si alloys which uses experimental results to estimate nucleation and growth kinetics. The goal of this work is to incorporate the micro-model into a macromodel to improve temperature history predictions a/nd provide a basis for more detailed microstructure and microporosity predictions. The model has been implemented in ProCAST{trademark}, a finite element based commercial casting analysis software.

• OSTI ID: 382488
• Journal Information: Scripta Materialia, Vol. 35, Issue 7; Other Information: PBD: 1 Oct 1996
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
33 ADVANCED PROPULSION SYSTEMS
ALUMINIUM ALLOYS
SOLIDIFICATION
MICROSTRUCTURE
SILICON ALLOYS
AUTOMOBILES
ENGINES
MATHEMATICAL MODELS
LIQUID METALS
CHEMICAL COMPOSITION
EUTECTICS
DUCTILITY
TENSILE PROPERTIES
HEAT FLUX
FUSION HEAT
NUCLEATION
KINETICS
PREDICTION EQUATIONS
POROSITY
FINITE ELEMENT METHOD