Al2O3-RARE EARTH OXIDE-ZrO2/HfO2 MATERIALS, AND METHODS OF MAKING AND USING THE SAME

Abstract

Al 2 O 3 -rare earth oxide-ZrO 2 /HfO 2 ceramics (including glasses, crystalline ceramics, and glass-ceramics) and methods of making the same. Ceramics according to the present disclosure can be made, formed as, or converted into glass beads, articles (e.g., plates), fibers, particles, and thin coatings. The particles and fibers are useful, for example, as thermal insulation, filler, or reinforcing material in composites (e.g., ceramic, metal, or polymeric matrix composites). The thin coatings can be useful, for example, as protective coatings in applications involving wear, as well as for thermal management. Certain ceramic particles according to the present disclosure can be are particularly useful as abrasive particles.

1 . A pavement marking, comprising:
 transparent microspheres comprising:
 between about 35 wt % to about 40 wt % of one or more metal oxides selected from lanthanide series oxides and yttrium oxide; 
 at least about 30 wt % Al 2 O 3 ; 
 at least 30 wt % of one or more metal oxides selected from the group consisting of ZrO 2 , TiO 2 , BaO, SrO, CaO, and MgO and mixtures thereof. 
   
     
     
         2 . The pavement marking of  claim 1 , wherein the microspheres comprise between about 5 wt % and about 30 wt % ZrO 2 . 
     
     
         3 . The pavement marking of  claim 2 , wherein the microspheres comprise at least 21 wt % of one or more metal oxides selected from the group consisting essentially of TiO 2 , BaO, SrO, CaO, and MgO. 
     
     
         4 . The pavement marking of  claim 1 , wherein the microspheres include at least 13 wt % of one or more metal oxides selected from the group consisting essentially of TiO 2  and CaO. 
     
     
         5 . The pavement marking of  claim 2 , wherein the microspheres include at least 10 wt % of CaO. 
     
     
         6 . The pavement marking of  claim 2 , wherein the microspheres comprise:
 2 to 20 wt % TiO 2 ; and   at least 9 wt % of CaO.   
     
     
         7 . A pavement marking, comprising:
 transparent microspheres comprising:   between about 35 wt % and about 41 wt % of one or more metal oxides selected from lanthanide series oxides and yttrium oxide;   at least about 30 wt % Al 2 O 3 ;   between about 5 wt % to about 30 wt % ZrO 2 , and   at least 24 wt % of one or more metal oxides selected from a group consisting essentially of TiO 2 , BaO, SrO, CaO, and MgO.   
     
     
         8 . A pavement marking, comprising:
 transparent microspheres comprising:   between about 20 wt % and about 39 wt % of one or more metal oxides selected from lanthanide series oxides and yttrium oxide;   at least about 30 wt % Al 2 O 3 , and   between about 5 and about 39 wt % ZrO 2 , and   at least 8 wt % CaO.   
     
     
         9 . The pavement marking of  claim 8 , wherein the transparent microspheres comprise:
 between about 20 wt % and about 37 wt % of one or more metal oxides selected from lanthanide series oxides and yttrium oxide,   between about 2 wt % and about 20 wt % TiO 2 , and   at least 19 wt % of one or more metal oxides selected from the group consisting essentially of ZrO 2 , BaO, SrO, CaO, and MgO.   
     
     
         10 . The pavement marking of  claim 8 , wherein the transparent microspheres comprise:
 between about 20 wt % and about 39 wt % of one or more metal oxides selected from lanthanide series oxides and yttrium oxide;   between about 2 wt % and about 20 wt % TiO 2 , and   at least 6 wt % CaO.   
     
     
         11 . The pavement marking of  claim 8 , wherein the pavement marking is a pavement marking tape.