An ultrastable cementitious material with nano-molecular veneer makes a cementitious material by blending 29 wt % to 40 wt % of a magnesium oxide dry powder containing 80 wt % to 98 wt % of magnesium oxide based on a final total weight of the cementitious material, with 14 wt % to 18 wt % of a magnesium chloride dissolved in water and reacting to form a liquid suspension, mixing from 2 to 10 minutes, adding a phosphorus-containing material, and allowing the liquid suspension to react into an amorphous phase cementitious material, wherein a portion of the amorphous phase cementitious material grows a plurality of crystals. The plurality of crystals are encapsulated by the amorphous phase cementitious material forming a nano-molecular veneer. A process to make the ultrastable cementitious material. A tile backer board incorporating the ultrastable cementitious material and a process for making the tile backer board.

A magnesium-based fly ash porous sound-absorbing material with a surface hydrophobically modified, and a preparation method thereof are provided. In the preparation method, a basic magnesium sulfate cement is adopted as a cementing agent and a fly ash is adopted as a mineral admixture to prepare a slurry; foaming is conducted through a physical foaming process in a foaming machine to obtain a foam; and the foam is mixed with the slurry, and a resulting mixture is poured and cured, and then subjected to a surface hydrophobic modification through vapor deposition to obtain the sound-absorbing material. The sound-absorbing material has a density of 251 kg/m.sup.3 to 306 kg/m.sup.3, a noise reduction coefficient (NRC) of 0.65 to 0.7, a compressive strength of 1.8 MPa to 2.2 MPa, and a water contact angle of 129° to 151°.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

Composite cellulosic products and processes for making same. In some embodiments, the composite cellulosic product can include a plurality of cellulosic substrates and an at least partially cured binder. Prior to curing, the binder can include a mixture formed by combining magnesium oxide, water, and magnesium chloride. A weight ratio of the magnesium oxide to the magnesium chloride in the binder can be at least 2.2:1 to 8.5:1.

Composite cellulosic products and processes for making same. In some embodiments, the composite cellulosic product can include a plurality of cellulosic substrates and an at least partially cured binder. Prior to curing, the binder can include a mixture formed by combining magnesium oxide, water, and magnesium chloride. A weight ratio of the magnesium oxide to the magnesium chloride in the binder can be at least 2.2:1 to 8.5:1.

Composite cellulosic products and processes for making same. In some embodiments, the composite cellulosic product can include a plurality of cellulosic substrates and an at least partially cured binder. Prior to curing, the binder can include a mixture formed by combining magnesium oxide, water, and magnesium chloride. A weight ratio of the magnesium oxide to the magnesium chloride in the binder can be at least 2.2:1 to 8.5:1.

This invention relates to three-dimensional printing. This invention in particularly relates to a method of fabricating a three-dimensional object using a support edifice and also using a mold material with structural additives. The support edifice is fabricated in the same crafting material as the final three-dimensional object in the same manner as the printing of the final three-dimensional object (mold and crafting in a layer by layer manner). This method enables the support edifice to also transform during post processing in the same manner as the final three-dimensional object, thus supporting the object until finished. The system for fabricating the object comprises a dual printhead comprising a first dispensing nozzle for depositing the filament material in a flowable fluid form and a second dispensing nozzle for depositing the crafting medium, which is in a paste form. The printhead can also include a heating system or a drying apparatus. The three-dimensional imaging process for making objects, preferably metal objects or ceramic objects, on a layer-by-layer basis under the control of a data processing system is disclosed. The printing of the three-dimensional object such as heavy objects or an object having different parts having a very thin gap or space. It is important to use different processing steps and/or material to print such three-dimensional objects. The present invention provides a solution by printing a support edifice comprising a special structural additive for the mold, and further the support edifice can be printed simultaneously while printing the mold and crafting-paste material on a layer-by-layer basis. The mold material is mixed with the structural additive. The structural additive is useful for prohibiting either fusing of the object with the support edifice, or in alternative embodiments, the fusing of one part of an object with another part of an object.