This application describes kits, methods, and systems of three dimensional printing. In some examples, described herein are three-dimensional object printing kits comprising a metallic or a ceramic build material, a polymeric binder dispersed in an aqueous liquid vehicle, and a boundary fluid comprising thermally expandable particles.

A manufacturing method which manufactures articles which have hollow areas inside them which are subject to their own internal vacuum. A 3-D printer can be located inside a vacuum chamber and the article(s) can be 3-D printed, thereby the hollow area inside each such article is subject to its own vacuum. When removed from the vacuum chamber, the article's hollow area remains subject to its own internal vacuum.

A method is presented for producing hollow microspheres of metal oxides (HMOMS) and/or hollow metal silicates microspheres (HMSMS) in a transforming solution. The transforming solution contains an atom M, or an M-ion, or a radical containing M. M in the transforming solution has the thermodynamic ability to replace silicon atoms in hollow silica microspheres (HSMS) and/or hollow glass microspheres (HGMS). The maximum temperature for transformation is set by the chemical physical properties of the transforming solution, and the viscosity of the silica in the walls of the HSMS and/or the glass in the walls of the HGMS. Viscosity, of enough magnitude, helps retain the desired shape of the hollow sphere as it is transformed to HMOMS and/or HMSMS. Non-spherical shapes can be produced by increasing the transformation temperature whereby the viscosity of the walls of the HSMS and/or the HGMS is reduced. Transformation can take place at a single temperature or at several temperatures, each temperature for a separate hold time.

Methods are presented for: 1. production of micro composite castings and continuous production of sheets of micro composites, both consisting of hollow spheres in a matrix, 2. harvesting of HMOMS and HMSMS, and 3. specialty castings for anisotropic properties using 3-dimensional printing

A graded multilayered composite comprises a metal matrix material having a first side and a second side opposite the first side. A first layer of microspheres is dispersed on the first side of the metal matrix material. A second layer of microspheres is dispersed on the second side of the metal matrix material.

A graded multilayered composite comprises a metal matrix material having a first side and a second side opposite the first side. A first layer of microspheres is dispersed on the first side of the metal matrix material. A second layer of microspheres is dispersed on the second side of the metal matrix material.

A multilayered material system includes at least one of a liner sheet and a cellular core, and a multilayered composite joined to the at least one of a liner sheet and a cellular core. The multilayered composite includes hollow microspheres dispersed within a metallic matrix material.

A multilayered material system includes at least one of a liner sheet and a cellular core, and a multilayered composite joined to the at least one of a liner sheet and a cellular core. The multilayered composite includes hollow microspheres dispersed within a metallic matrix material.

The present invention relates to a gear wheel containing at least one sintered material having a porosity, the gear wheel having, in addition to the porosity, another noise-reducing means.

A structured multi-phase composite which include a metal phase, and a low stiffness, high thermal conductivity phase or encapsulated phase change material, that are arranged to create a composite having high thermal conductivity, having reduced/controlled stiffness, and a low CTE to reduce thermal stresses in the composite when exposed to cyclic thermal loads. The structured multi-phase composite is useful for use in structures such as, but not limited to, high speed engine ducts, exhaust-impinged structures, heat exchangers, electrical boxes, heat sinks, and heat spreaders.

A metal matrix composite is provided, including a metal, inorganic particles, and discontinuous fibers. The inorganic particles and the discontinuous fibers are dispersed in the metal. The metal includes aluminum, magnesium, or alloys thereof. The inorganic particles have an envelope density that is at least 30% less than a density of the metal. The metal matrix composite has a lower envelope density than the matrix metal while retaining a substantial amount of the mechanical properties of the metal.