CSIRO and Amaero modernise die cast tooling with slick conformal cooling solution and additive manufacturing

Australia’s national science agency, CSIRO, has used virtual reality to crack a stubborn die casting problem, developing a solution that uses conformal cooling.

Working with Melbourne small business, Amaero Engineering Pty Ltd, researchers at CSIRO’s Lab22 Innovation Centre, one of Australia’s leading centres for metallic additive manufacturing, developed the innovative solution using some clever simulations.

Program Manager at Amaero, Mr Sam Tartaglia, said the company, which specialises in additively manufactured high performance parts, saw an opportunity to explore the use of conformal cooling in 3D printed die cast tooling, using computational modelling.

“High pressure die casting (HPDC) is by far the most popular manufacturing route for mass-produced near-net-shape metal parts,” Mr Tartaglia said.

“The process forces molten metal into a die cavity via a series of passages or ‘runners’, which include the ‘sprue area’, to produce a part in the shape of the cavity before the final solidified product is removed,” he said.

“We were looking to find a solution to a stubborn problem that was challenging one of our clients – the sprue area running too hot.

“The issue was causing prolonged cycle times, with the die taking longer to cool between shots, and frequent production line stoppages”.

Using Finite Element Method computational modelling, the partners explored optimising the geometry of conformed cooling channels of the H13 die tools for the sprue area using additive manufacturing.

Principal Research Engineer at CSIRO, Dayalan Gunasegaram, said the team focused on coupled heat transfer and stress analysis.

“We used the modelling to assess the effectiveness of conformal cooling, compared to traditional tooling used in industry,” Dr Gunasegaram said.

Apart from giving the casting and runners their shape, HPDC tools perform the task of removing heat from the molten metal via the water circulating through the cooling channels within the tools.

The problem, however, is that traditional machining methods used to drill out these channels can only produce straight holes in limited locations, and this diminishes the effectiveness of the heat removal strategy.

Conformal cooling, by contrast, uses coolant channels that follow the complex contours of intricate part designs, offering much better cooling efficiency.

Additive manufacturing makes it possible to build parts with highly optimised, complex geometries – perfect for creating conformal cooling channels in a tool.

Tartaglia said conformal cooling can translate to significant productivity improvements along with improved product quality.

“This capability has potential applications in plastic injection moulding, metal die casting tools and other metal tooling used in manufacturing” he said.

Gunasegaram said the project, partly funded by an Innovation Connections grant through the Australian Government’s Entrepreneurs’ Program for Small and Medium Enterprises (SMEs), is an example of how CSIRO can add commercial value to businesses working in the advanced manufacturing space.

Amaero, who have diversified into additively manufactured tooling as a new business area, will have a virtual booth at the upcoming North American Die Casting Association’s Die Casting Congress & Tabletop on October 20-22.