초록 ▼

Low or negative thermal expansion compounds are described having a formula of A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12. It currently is believed that y can vary from about 0 to about 2, x equals the sum of y and z and varies from about 0.1 to about 1.9. Withou

Low or negative thermal expansion compounds are described having a formula of A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12. It currently is believed that y can vary from about 0 to about 2, x equals the sum of y and z and varies from about 0.1 to about 1.9. Without limitation, novel compounds satisfying the formula A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12 where y=0 may be selected from the group consisting of Al.sub.1.5 In.sub.0.5 W.sub.3 O.sub.12, Al.sub.1.6 In.sub.0.4 W.sub.3 O.sub.12, Al.sub.1.7 In.sub.0.3 W.sub.3 O.sub.12, Al.sub.1.8 In.sub.0.2 W.sub.3 O.sub.12, YAlW.sub.3 O.sub.12, ScAlW.sub.3 O.sub.12, ScGaW.sub.3 O.sub.12, ScInW.sub.3 O.sub.12, ScHoW.sub.3 O.sub.12, ScYbMo.sub.3 O.sub.12 and ErInW.sub.3 O.sub.12. Without limitation, novel compounds satisfying the formula A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12 where y=2 may be selected from the group consisting of Hf.sub.2 WP.sub.2 O.sub.12 and Hf.sub.2 MoP.sub.2 O.sub.12. The present invention also provides compositions useful for decreasing the positive thermal expansion of a material or materials included in the compositions. The compositions comprise at least a first material and a second material where the first material has low or negative thermal expansion properties and the second material exhibits positive thermal expansion. Novel compositions and methods for making and using such compositions can be made using a first material selected, without limitation, from the group consisting of Al.sub.2 W.sub.3 O.sub.12, Al.sub.2 Mo.sub.3 O.sub.12, In.sub.2 W.sub.3 O.sub.12, Al.sub.1.5 In.sub.0.5 W.sub.3 O.sub.12, Al.sub.1.6 In.sub.0.4 W.sub.3 O.sub.12, Al.sub.1.7 In.sub.0.3 W.sub.3 O.sub.12, Al.sub.1.8 In.sub.0.2 W.sub.3 O.sub.12, YAlW.sub.3 O.sub.12, ScAlW.sub.3 O.sub.12, ScGaW.sub.3 O.sub.12, ScInW.sub.3 O.sub.12, ScHoW.sub.3 O.sub.12, ScYbMo.sub.3 O.sub.12, ErInW.sub.3 O.sub.12, Al.sub.1.68 Sc.sub.0.02 In.sub.0.3 W.sub.3 O.sub.12, Zr.sub.2 WP.sub.2 O.sub.12, Zr.sub.2 MoP.sub.2 O.sub.12, Hf.sub.2 WP.sub.2 O.sub.12 and Hf.sub.2 MoP.sub.2 O.sub.12. A general method for making compounds having low or negative thermal expansion, and compositions containing such compounds, also is described. The first step of the method comprises purposefully designing compounds to be low or negative thermal expansion compounds according to rules derived empirically. The second step comprises making those compounds designed according to the rules. Examples of negative thermal expansion materials made by such method include NbO.sub.2 F and TaO.sub.2 F.

대표청구항 ▼

[ We claim:] [1.] A compound according to the formula A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12 where A.sup.3+ is a metal having an oxidation state of plus 3, A.sup.4+ is a metal having an oxidation state of plus 4, M.sup.3+ is a metal having an oxidation state

[ We claim:] [1.] A compound according to the formula A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12 where A.sup.3+ is a metal having an oxidation state of plus 3, A.sup.4+ is a metal having an oxidation state of plus 4, M.sup.3+ is a metal having an oxidation state of plus 3, M.sup.6+ is a metal having an oxidation state of plus 6, y varies from about 0 to about 2, x is equal to the sum of y and z and varies from about 0.1 to about 1.9.