Oxynitride ceramic material with lithium addition
An oxynitride ceramic material includes a Ca 7-8 Al 15-15.5 Si 17-18 O 56-57 N 5-6 material and a Li 6-4 La 3 Zr 1.4 Ta 0.6 O 12 material in an amount of 10 to 80 percent by weight (wt. %) based on a total weight of the oxynitride ceramic material. The oxynitride ceramic material is crystalline and includes phases including a lanthanum zirconium oxide (La 2 Zr 2 O 7 ) phase, a lanthanum tantalum oxynitride (LaTaON 2 ) phase, a lithium aluminate (LiAlO 2 ) phase, a zirconium silicate (ZrSiO 2 ) phase, and a lithium aluminosilicate (LiAlSi 3 O 8 ) phase.
1 . An oxynitride ceramic material, comprising:
a Ca 7-8 Al 15-15.5 Si 17-18 O 56-57 N 5-6 material; and
a Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 material in an amount of 10 to 80 percent by weight (wt. %) based on a total weight of the oxynitride ceramic material,
wherein the oxynitride ceramic material is crystalline and comprises phases including a lanthanum zirconium oxide (La 2 Zr 2 O 7 ) phase, a lanthanum tantalum oxynitride (LaTaON 2 ) phase, a lithium aluminate (LiAlO 2 ) phase, a zirconium silicate (ZrSiO 2 ) phase, and a lithium aluminosilicate (LiAlSi 3 O 8 ) phase.
2 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material has a density of 2.7 to 4 g/cm 3 .
3 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material has a thermal conductivity of 1.5 to 1.8 W/m·K.
4 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material has a thermal expansion of 4.7 to 5.6 ppm/° C.
5 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material has a first activation energy of 0.7 to 1 eV.
6 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material has a second activation energy of 0.8 to 1.1 eV.
7 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material comprises nodules having a diameter of 0.1 to 5 μm and voids having a length of 5 to 50 μm.
8 . The oxynitride ceramic material of claim 1 , wherein ions are transported within the oxynitride ceramic material via correlated barrier hopping.
9 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material comprises the La 2 Zr 2 O 7 phase in an amount of at least 20 wt. % based on a total weight of the phases.
10 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material comprises the Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 material in an amount of 75 wt. % based on a total weight of the oxynitride ceramic material.
11 . The oxynitride ceramic material of claim 10 , wherein the oxynitride ceramic material has a density of 3.8 to 4 g/cm 3 .
12 . The oxynitride ceramic material of claim 10 , wherein the oxynitride ceramic material has a thermal conductivity of 1.5 to 1.7 W/m·K.
13 . The oxynitride ceramic material of claim 10 , wherein the oxynitride ceramic material has a thermal expansion of 4.8 to 5 ppm/° C.
14 . The oxynitride ceramic material of claim 10 , wherein the oxynitride ceramic material has a first activation energy of 0.85 to 0.95 eV.
15 . The oxynitride ceramic material of claim 10 , wherein the oxynitride ceramic material has a second activation energy of 0.97 to 1.07 eV.
16 . The oxynitride ceramic material of claim 1 , wherein the oxynitride ceramic material is made by a process comprising:
mixing the Ca 7-8 Al 15-15.5 Si 17-18 O 56-57 N 5-6 material and the Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 material with a probe sonicator for 30 to 90 minutes to form a homogenous mixture; and
sintering the homogeneous mixture in a die at a temperature of 850 to 950° C. for 20 to 40 minutes to form the oxynitride ceramic material,
wherein the sintering is spark plasma sintering,
wherein a heating rate during the sintering is 80 to 120° C./min.
17 . The oxynitride ceramic material of claim 16 , wherein the die is pressurized to to 35 MPa.
18 . The oxynitride ceramic material of claim 16 , wherein the die is placed in a vacuum having a pressure of 4×10 −2 to 5×10 −2 mbar during the sintering.
19 . The oxynitride ceramic material of claim 16 , further comprising:
melting and casting Ca 7-8 Al 15.1 Si 17.5 O 56.5 N 5.5 at a temperature of 1600 to 1700° C. to form a Ca 7-8 Al 15.1 Si 17-8 O 56.5 N 5.5 glass before the mixing.
20 . The oxynitride ceramic material of claim 19 , further comprising:
ball-milling the Ca 7.5 Al 15.1 Si 17-8 O 56.5 N 5.5 glass for 4 to 8 hours to form the Ca 7.5 Al 15.1 Si 17.5 O 56.5 N 5.5 material before the mixing,
wherein the Ca 7.5 Al 15.1 Si 17-8 O 56.5 N 5.5 material is a powder.