Method of making lightweight high performance ceramic material

1. A method of making a sintered ceramic composition comprising:

a. providing a powder comprising at least 50 wt. % boron carbide and 0.05 wt. % to 30 wt. % of at least one oxide selected from the group consisting of oxides of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu;

b. milling said powder to form a milled powder;

c. drying said milled powder to form a milled, dried powder; and

d. consolidating said milled, dried powder at a temperature in the range of 1500° C. to 2200° C. to form a sintered ceramic composition having a density of at least 90% of theoretical density,

wherein at least one of said providing step and said milling step introduces Zr into said powder so that said sintered ceramic composition comprises zirconium diboride in an amount in the range of 1 wt. % to 10 wt. %.

2. A method of making a sintered ceramic composition in accordance with claim 1 wherein said powder comprises 0.1 wt. % to 20 wt. % of said at least one oxide.

3. A method of making a sintered ceramic composition in accordance with claim 2 wherein said powder comprises 0.5 wt. % to 10 wt. % of said at least one oxide.

4. A method of making a sintered ceramic composition in accordance with claim 3 wherein said powder comprises 1 wt. % to 5 wt. % of said at least one oxide.

5. A method of making a sintered ceramic composition in accordance with claim 1 wherein said powder further comprises 0.05 wt. % to 30 wt. % of at least one material selected from the group consisting of: elemental B and C; oxides of Li, Mg, Al, Si, Ca, Sc, and Sr; and oxides, carbides, nitrides, and borides of Ti, V, Zr, Nb, Mo, Hf, Ta, and W.

6. A method of making a sintered ceramic composition in accordance with claim 5 wherein said powder comprises 0.1 wt. % to 20 wt. % of said at least one material.

7. A method of making a sintered ceramic composition in accordance with claim 6 wherein said powder comprises 0.5 wt. % to 10 wt. % of said at least one material.

8. A method of making a sintered ceramic composition in accordance with claim 7 wherein said powder comprises 1 wt. % to 5 wt. % of said at least one material.

9. A method of making a sintered ceramic composition in accordance with claim 1 wherein said milling step is carried out using a milling medium comprising zirconium.

10. A method of making a sintered ceramic composition in accordance with claim 1 wherein said consolidating step is carried out at a temperature in the range of 1600° C. to 2100° C.

11. A method of making a sintered ceramic composition in accordance with claim 10 wherein said consolidating step is carried out at a temperature in the range of 1800° C. to 2000° C.

12. A method of making a sintered ceramic composition in accordance with claim 11 wherein said consolidating step is carried out at a temperature in the range of 1850° C. to 1950° C.

13. A method of making a sintered ceramic composition in accordance with claim 1 wherein said consolidating step forms a sintered ceramic composition that has a density of at least 95% of theoretical density.

14. A method of making a sintered ceramic composition in accordance with claim 13 wherein said consolidating step forms a sintered ceramic composition that has a density of at least 98% of theoretical density.

15. A method of making a sintered ceramic composition in accordance with claim 14 wherein said consolidating step forms a sintered ceramic composition that has a density of at least 99.5% of theoretical density.

16. A method of making a sintered ceramic composition in accordance with claim 15 wherein said consolidating step forms a sintered ceramic composition that has a density of 100% of theoretical density.