Negative thermal expansion materials including method of preparation and uses therefor

A ceramic body comprising A2P2WO12, and a crystalline or non-crystalline oxide phase, including a glassy phase, which contains a metal selected from the group consisting of alkaline earth metals, alkali metals, manganese, iron, cobalt, copper, zinc, aluminum, gallium, bismuth, yttrium, lanthanide metals, scandium, niobium, titanium, and nickel, further compromising AW2O8, wherein A is selected from the group consisting of Zr and Hf.

A ceramic body comprising two phases having negative coefficients of thermal expansion, wherein one of the phases has a room temperature coefficient of thermal expansion more negative than −50×10−7° C.−1.

A method of raising the negative thermal expansion (i.e. making the thermal expansion less negative) of a ceramic body comprising a phase having a room temperature coefficient of thermal expansion more negative than −50×10−7° C.−1 comprising mixing together the first phase with at least a second phase or precursors of the first phase and at least the second phase, the second phase having a negative thermal expansion less negative than −50×10−7° C.−1.

A method of raising the negative thermal expansion (i.e. making the thermal expansion less negative) of a ceramic body comprising a phase having a room temperature coefficient of thermal expansion more negative than −50×10−7° C.−1 comprising mixing together the first phase with at least a second phase or precursors of the first phase and at least the second phase, the second phase having a negative thermal expansion less negative than −50×10−7° C.−1, wherein the material does not exhibit microcracking.

A method of raising the negative thermal expansion (i.e. making the thermal expansion less negative) of a ceramic body comprising a phase having a room temperature coefficient of thermal expansion more negative than −50×10−7° C.−1 comprising mixing together the first phase with at least a second phase or precursors of the first phase and at least the second phase, the second phase having a negative thermal expansion less negative than −50×10−7° C.−1, wherein one phase has the composition AX2O8, where A is selected from the group consisting of zirconium and hafnium, and X is selected from the group consisting of tungsten and molybdenum, and wherein the second phase has the composition M2B3O12 where M is selected from the group including aluminum, scandium, indium, yttrium, the lanthanide metals, zirconium, and hafnium, and where B is selected from the group consisting of tungsten, molybdenum, and phosphorus, and where M and B are selected such that the compound M2B3O12 has a negative CTE.