Abstract: A method for fabricating an infiltrated object of a desired shape having a high volume fraction of infiltrant using an additively manufactured preform. Using an additive manufacturing technique, the preform is formed with graded macro-porosity. When infiltrated, the void volume of the macro-porosity is filled with infiltrant Optionally, the void volume may be varied across the profile of the object to create a gradient of mechanical properties in the infiltrated object.

Abstract: A method of maintaining part geometry fidelity during infiltration of a metallic preform. The preform and an infiltration barrier are formed, either independently or together during an additive manufacturing process. The infiltration barrier prevents infiltrant from bleeding out from the preform where it is present, thus protecting fine geometries that would otherwise be filled with infiltrant.

Abstract: A method for the manufacture of a three-dimensional object includes the steps of forming a mixture that contains a binder and a least one of aluminum or a first aluminum-base alloy into a green composite, removing the binder from said green composite, forming a porous preform structure, reacting the aluminum or first aluminum base alloy with nitrogen to form a rigid skeleton and infiltrating the porous structure with molten aluminum or second aluminum base alloy to form the three-dimensional object with near theoretical density. The green composite may be formed by an additive process such as computer aided rapid prototyping, for example selective laser sintering. The method facilitates the rapid manufacture of aluminum components by an inexpensive technique that provides high dimensional stability and high density.