Sedimentation casting of wear resistant metal matrix composites

A new sand casting technique to produce particle reinforced composites has been developed. It is called “the drawer casting technique”. The technique is based on sedimentation casting and gives a high concentration of particulates at and below the working surface of the component. Two models that assisted the development of the drawer casting technique are described. It is shown that WC reinforcing particles settle in the bottom of the mould quickly to form a sediment bed. The critical flow velocity required to avoid sediment bed particle motion as the mould is filled is calculated. The use of the technique for the production of materials with a flat wear resistant working surface consisting of a white cast iron matrix reinforced with ex situ (WC) and in situ formed transition and refractory metal carbide particles is described.