Vanadium garnet materials

Claim 1

A vanadium garnet composition involving V 2 O 3 , CaO and SiO 2 wherein the shaded area circumscribed by ABCDEFGHIJ as shown in the disclosed FIGURE for a ternary composition diagram of V 2 O 3 , CaO and SiO 2 represents compositions of liquids with which said vanadium garnet is in equilibrium on the liquidus surface and from which said vanadium garnet phase is crystallized, and wherein the amounts of V 2 O 3 , CaO and SiO 2 are characterized as shown in the table below: ______________________________________ Coordinates (wt %) Vertices V.sub.2 O.sub.3 CaO SiO.sub.2 ______________________________________ A 26.5 27.5 46.0 B 23.7 32.5 43.8 C 17.2 43.8 39.0 D 17.0 45.0 38.0 E 26.2 43.8 30.0 F 21.3 46.7 25.0 G 31.0 50.0 19.0 H 46.2 41.8 12.5 I 47.5 38.8 13.7 J 40.0 32.5 27.5. ______________________________________

Claim 5

A method of preparing a vanadium garnet material involving V 2 O 3 , CaO and SiO 2 from a liquid with which said vanadium garnet is in equilibrium on the liquidus surface and wherein said liquid has a composition that falls within a polygon shaped shaded area ABCDEFGHIJ as shown in the disclosed FIGURE for a ternary composition diagram of V 2 O 3 , CaO and SiO 2 comprising the steps of: (1) heating V 2 O 5 powder having a particle size of less than about 50 microns in an atmosphere in which the partial pressure of oxygen is in the range of 10 -5 to 10 -10 atmospheres while gradually increasing the temperature over a temperature range of about 600° C. to 1300° C. and holding the final temperature for a period to ensure complete reduction of all vanadium to V 3+ ; (2) heating CaO and SiO 2 powders each having a particle size of less than about 50 microns for a period of about 10 to 14 hrs at a temperature in the range of about 1000° C. to (3) thoroughly grinding together an amount of V 2 O 3 from (1) in the range of about 17 to 47.5 wt. %, with an amount of CaO from (2) in the range of about 27.5 to 50 wt. %, and an amount of SiO 2 from (2) in the range of about 12.5 to 46 Wt. % to produce a mixture having a grain size of less than about 50 microns, (4) pelletizing the mixture from (3) at a pressure of about 5,000 psi; and (5) heating the pellets from (4) at a temperature in the range of about 1100° C. to 1400° C. for a period in the range of about 12 to 48 hrs in an atmosphere in which the partial pressure of oxygen is in the range of 10 -10 to 10 -5 atmosphere, and crystallizing out said vanadium garnet phase.

Claim 6

A method of preparing a vanadium garnet material involving V 2 O 3 , CaO and SiO 2 from a liquid with which said vanadium garnet is in equilibrium on the liquidus surface and wherein said liquid has a composition that falls within a polygon shaped shaded area ABCDEFGHIJ as shown in the disclosed FIGURE for a ternary composition diagram of V 2 O 3 , CaO and SiO 2 comprising the steps of: (1) heating V 2 O 5 powder having a particle size of less than about 50 microns in an atmosphere in which the partial pressure of oxygen is in the range of 10 -5 to 10 -10 atmospheres while gradually increasing the temperature over a temperature range of about 600° C. to 1300° C. and holding the final temperature for a period to ensure complete reduction of all vanadium to V 3+ ; (2) heating CaO and SiO 2 powders each having a particle size of less than about 50 microns for a period of about 10 to 14 hrs at a temperature in the range of about 1000° C. to (3) thoroughly grinding together an amount of V 2 O 3 from (1) in the range of about 17 to 47.5 wt. %, with an amount of CaO from (2) in the range of about 27.5 to 50 wt. %, and an amount of SiO 2 from (2) in the range of about 12.5 to 46 Wt. % to produce a mixture having a grain size of less than about 50 microns, (4) pelletizing the mixture from (3) at a pressure of about 5,000 psi; and (5) heating the pellets from (4) at a temperature in the range of about 1100° C. to 1400° C. for a period in the range of about 12 to 48 hrs in an atmosphere in which the partial pressure of oxygen is in the range of 10 -10 to 10 -5 atmosphere, and crystallizing out said vanadium garnet phase.