A new category of hypereutectic aluminum liners, made by PM route is now available on the market (SILITEC) and it is successfully applied to high-pressure die casting process to produce open deck cylinder blocks. The claimed achievable engine performances over cast-iron liners (weight saving, reduction of oil consumption, optimal heat transfer, wear and friction losses reduction) justify the interest of automotive industry in developing such a technology.
The paper will present the experience and the achieved results in permanent mold gravity casting with Silitec liners, where metal flow definition and temperature distribution control make the casting technique more challenging for the manufacturing of closed deck cylinder blocks.
A full experimentation based on Design Of Experiment (D.O.E.) methodology was carried out by adopting different process parameters and different external surface of the liners to maximize the metallurgical bonding between liners and crankcase without having liner melting and deformations.
A FEM thermo-structural analysis of the engine was performed in order to evaluate the influence of bonding on the engine performance.