“We know in the laboratory that if we pull all the air out of the mold just before the molten metal flows in, we can eliminate the bubbles,” Luo said. “Without bubbles, we can design thinner parts that are just as strong and durable, but with less metal and lighter weight. Tere are other benefits, as well, because the new process allows us to heat treat parts after they are cast, which will improve their performance in service.” The group also will be working on a shortened
solution heat treatment to improve mechanical proper-
ties cost efficiently. A simple T5 heat treatment (where castings are cooled from an elevated temperature and artificially aged) has shown in preliminary work to in- crease yield strength by 40% for E380-type alloys. Now researchers want to see if a shortened T6 heat treatment (where castings are solution heat treated and artificially aged) can be developed to achieve even better properties in 300 series aluminum. An important part of the two-year project will be enhancing the ability of computer models to predict the performance of aluminum diecast parts by combining information about the microstructure of the metal with a host of design and production parameters. Te process, called integrated computational materials engineering (ICME), has great potential for reducing the time it takes to design and qualify new components for vehicles and will address some of the key challenges in implementing thin- wall diecasting technologies: die design, process control, casting design and process simulation. Currently, castings are designed using the minimum
properties of alloys as a baseline for the entire part. Te ICME approach will allow designers to pinpoint higher or lower minimum properties to localized regions. Te aim is to connect the thermodynamic prediction of alloy composition and heat treatments to process model-
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