· Técnicas de simulación avanzadas ·
J. Fang*, H. D. Brody* and J. E. Morral**
* University of Connecticut, USA, ** The Ohio State University, USA
67th World Foundry Congress
An empirical relation has been developed for Al-Si-Cu-Mg alloys to
facilitate the computer aided design of casting and heat treatment
processes that can be used to achieve specified tensile properties in
critical locations of cast components. The empirical relation is one
element of a collaborative program to develop, verify and market an
integrated system of software, databases, and design rules to enable
quantitative prediction and optimization of the heat treatment of aluminum
castings to increase quality, increase productivity, reduce heat treatment
cycle times and reduce energy consumption.
End-chilled cast plates were used to produce as-cast microstructures with
secondary dendrite arm spacing (das) ranging from 20 micrometers to 70
micrometers and volumetric porosity (%P) ranging up to 1.2%. The
nominal composition studied was Al-7%Si-3.5%Cu-0.33%Mg-0.5%Fe.
Coupons cut from the cast plates were given solutionizing times (θS) from
0 to 32 hours, quenched, aged, machined into cylindrical test bars, and
tested in tension. Ultimate tensile strength, yield strength, and % plastic
elongation were recorded. Three parameters were selected to represent
the casting and heat treating process conditions and the tensile strength
(TS) was fit to an expression of the form
( ) d c P b das a TS S + ⋅ + + ⋅ + ⋅ = θ % 1 ln
where , , , c b a and d are the adjustable parameters.
The measured tensile properties of newly cast plates were compared to
the tensile properties predicted by the empirical model derived from the
original set of cast plates. The slopes of the correlation curves are one
with R2 > 0.95 for the compositions for which duplicate plates were cast.
