YAG lasing systems and methods
View Patent ↗Lasing systems utilizing YAG and methods for producing a YAG suitable for lasing are provided. The lasing system comprises a laser activator and a laser host material is provided. The laser host material comprises a transparent polycrystalline yttrium aluminum garnet material defined by a low porosity of less than about 3 ppm.
1. A method of producing polycrystalline yttrium aluminum garnet, comprising:
providing a compact comprising at least one powder selected from undoped yttrium aluminum garnet, doped yttrium aluminum garnet, a powder mixture having undoped yttrium aluminum perovskite, and a powder mixture having doped yttrium aluminum perovskite;
sintering the compact in flowing oxygen at temperatures of between about 1500° C. to about 1700° C. such that sintered yttrium aluminum garnet is formed; and
hot isostatically pressing the sintered yttrium aluminum garnet at temperatures of between about 1400° C. to about 1600° C. for about 5 to about 20 hours and at pressures sufficient to form a transparent polycrystalline yttrium aluminum garnet is formed having a porosity between less than about 3 ppm, and a mean grain size of about 1 to about 2 μm.
2. A method of producing polycrystalline yttrium aluminum garnet, comprising:
providing a compact comprising at least one powder selected from undoped yttrium aluminum garnet, doped yttrium aluminum garnet, a powder mixture having undoped yttrium aluminum perovskite, and a powder mixture having doped yttrium aluminum perovskite;
sintering the compact in flowing oxygen at temperatures of between about 1500° C. to about 1700° C. for about 5 to about 20 hours such that sintered yttrium aluminum garnet is formed; and
hot isostatically pressing the sintered yttrium aluminum garnet at temperatures of between about 1400° C. to about 1600° C. and at pressures sufficient to form a transparent polycrystalline yttrium aluminum garnet is formed having a porosity between less than about 3 ppm, and a mean grain size of about 1 to about 2 μm.
3. A method according to claim 2 wherein the compact is sintered in flowing oxygen at temperatures of between about 1550 to about 1650° C.
4. A method according to claim 2 wherein the transparent polycrystalline yttrium aluminum garnet comprises a porosity of about 1 ppm.
5. A method according to claim 2 wherein the sintered yttrium aluminum garnet is hot isostatically pressed at a pressure between about 25 to about 30 ksi.
6. A method according to claim 2 wherein the sintered yttrium aluminum garnet is hot isostatically pressed at temperatures of between about 1450 to about 1550 ° C.
7. A method according to claim 2 wherein the at least one powder of the compact is cold isostatically pressed or is slip casted.
8. A method according to claim 2 further comprising adding about 0.10 to about 0.15 weight percent colloidal silica having a purity of about 99.9% or greater.
9. A method according to claim 2 wherein the sintering is defined by a heating rate of about 5 to about 15° C/minute.