An abrasive article includes a body having a bond material extending throughout the body and abrasive particles contained in the bond material. The bond material can include aluminum oxide (Al.sub.2O.sub.3) and lithium oxide (Li.sub.2O). In an embodiment, the bond material can include a ratio (Al.sub.2O.sub.3/Li.sub.2O) of a content of aluminum oxide (Al.sub.2O.sub.3) relative to a content of lithium oxide (Li.sub.2O), based on weight percent, of greater than 11.5 and at most 20. In another embodiment, the abrasive article can have a versatility factor of greater than 1.90.

ZrO.sub.2-toughened glass ceramics having high molar fractions of tetragonal ZrO2 and fracture toughness value of greater than 2 MPa.Math.m.sup.1/2. The glass ceramic may also include also contain other secondary phases that may be beneficial for toughening or for strengthening through an ion exchange process. Additional second phases may also decrease the coefficient of thermal expansion of the glass ceramic. A method of making such glass ceramics is also provided.

A composite material is provided that includes at least one first material and particles. The particles have a negative coefficient of thermal expansion and the particles have a sphericity of at least 0.7. The composite material includes at least 30 vol % of the particles at a particle size of d.sub.501.0 m or at least 40 vol % of the composite material at a particle size d.sub.50>1.0 m.

A glass-ceramic-ferrite composition contains glass, a ceramic filler, and NiZnCu ferrite. The glass contains about 0.5% by weight or more of R.sub.2O, where R is at least one selected from the group consisting of Li, Na, and K; about 5.0% by weight or less of Al.sub.2O.sub.3; about 10.0% by weight or more of B.sub.2O.sub.3; and about 85.0% by weight or less of SiO.sub.2 on the basis of the weight of the glass. The NiZnCu ferrite accounts for about 58% to 64% by weight of the glass-ceramic-ferrite composition. The ceramic filler contains quartz and, in some cases, forsterite. The quartz accounts for about 4% to 13% by weight of the glass-ceramic-ferrite composition. The forsterite accounts for about 6% by weight or less of the glass-ceramic-ferrite composition.

A mixture including glass fragments is located in a containment vessel and is processed in a kiln to form a commercially useful building product. The mixture is initially heated over a first time period to a first temperature intermediate the glass transition point temperature and about 950? C. or 1,100? C. (Section A). At the first temperature the glass fragments slump and bond to each other and the mixture is soaked at this temperature for a second time period (Section B). After reducing the temperature (Section C), the mixture is annealed for another time period (Section D). Finally, the kiln is cooled to allow the mixture to be removed (Section E).

A ceramic circuit board includes: a ceramic board; and an internal conductor disposed in the ceramic board, in which the ceramic board contains glass, a willemite filler, and an alumina filler, and an average particle diameter of the willemite filler is larger than an average particle diameter of the alumina filler.

A low K value, high Q value, low firing dielectric material and method of forming a fired dielectric material. The dielectric material can be fired below 950 C. or below 1100 C., has a K value of less than about 8 at 10-30 GHz and a Q value of greater than 500 or greater than 1000 at 10-30 GHz. The dielectric material includes, before firing a solids portion including 10-95 wt % or 10-99 wt % silica powder and 5-90 wt % or 1-90 wt % glass component. The glass component includes 50-90 mole % SiO.sub.2, 5-35 mole % or 0.1-35 mole % B.sub.2O.sub.3, 0.1-10 mole % or 0.1-25 mole % Al.sub.2O.sub.3, 0.1-10 mole % K.sub.2O, 0.1-10 mole % Na.sub.2O, 0.1-20 mole % Li.sub.2O, 0.1-30 mole % F. The total amount of Li.sub.2O+Na.sub.2O+K.sub.2O is 0.1-30 mole % of the glass component. The silica powder can be amorphous or crystalline.

A method of forming a macrocomposite including dispersing or immersing a first material in a second material. The first material includes a stone and the second material a glass; or the first material may be glass and the second material stone. The macrcocomposite may further include metal. Preferably, the macrocomposite does not include an organic resin, an adhesive, or a polymer.

Provided is a ceramic powder having precipitated therein -eucryptite or a -quartz solid solution as a main crystal phase, having an average particle diameter D.sub.50 of 20 m or less, and having a negative thermal expansion coefficient in a range of from 30 C. to 300 C.

A method of manufacturing a polarizing glass sheet includes subjecting, while heating, a glass preform sheet containing metal halide particles to down-drawing, to thereby provide a glass member having stretched metal halide particles dispersed in an aligned manner in a glass matrix, and subjecting the glass member to reduction treatment to reduce the stretched metal halide particles, to thereby provide a polarizing glass sheet. A shape of the glass preform sheet during the down-drawing satisfies a relationship of the following expression:

L.sub.1/W.sub.11.0

where L.sub.1 represents a length between a portion in which a width of the glass preform sheet has changed to 0.8 times an original width and a portion in which the width of the glass preform sheet has changed to 0.2 times the original width W.sub.0, and W.sub.1 represents a length equivalent to 0.5 times the original width W.sub.0 of the glass preform sheet.