Assessment of a controlled solidification aluminium investment casting technique for use in helicopter gearboxes

A higher degree of mechanical property scatter, as measured by Weibull Modulus and the Coefficient of Variance (CV), was observed between the TGB casting and the cast plates inferring the design of the filling system used by the foundry had not been optimised resulting in higher metal flow and surface turbulence and a greater likelihood of bifilms occurring within the casting.