Abstract: Methods and systems (2) are disclosed for making articles (114) by three-dimensional printing. The methods include selectively printing by jet deposition on successive layers (4) of a build material powder (10) at least one of a first binder fluid and a second binder fluid. At least one of the first and second binder fluids includes a particulate matter (16) having mean particle size diameter which is less than that of the build material powder (10). The first binder fluid is characteristically different from the second binder fluid. The particulate matter (16) selectively deposited with a binder fluid can be used to locally tailor the physical properties of the article (114), e.g. by alloying with the build material powder, increasing densification, acting as a local infiltrant or infiltrant stop during heat treatment, locally modulating the local stress fields (e.g. by a mismatch of thermal coefficients of expansion), etc.

Abstract: Methods and systems (20) are disclosed for making articles by three-dimensional printing. The methods include three-dimensionally printing articles by selectively jet-depositing a particle-bearing binder fluid (14) upon successive layers (4) of a build material powder (10) such that the particles (16) deposited with the binder fluid (14) increase the apparent density of the as-printed article. The particulate matter (16) of the binder fluid (12) is smaller than the mean particle size of the build material powder (10). Preferably, this jet-deposited particulate matter (16) has a mean particle size that is larger than about 1 to and smaller than or equal to 50 microns. The jet-deposited matter (16) acts to fill in the interparticle interstices of the build material powder (10) thereby simultaneously increasing the density of the printed article and improving its surface roughness and contour resolution, which in turn, improves the surface finish of the final article.