A piezoelectric element includes: a piezoelectric ceramic which has a perovskite compound expressed by the composition formula Li.sub.xNa.sub.yK.sub.1−x−yNbO.sub.3 (where 0.02<x≤0.1, 0.02<x+y≤1) as its primary component and which contains at least one of alkali earth metal selected from the group consisting of calcium, strontium, and barium, as well as silver, wherein the piezoelectric ceramic contains LiNbO.sub.3 at the surface but contains no or less LiNbO.sub.3 in the inner portion which is 5 μm or deeper from the surface, than at the surface; and at least one pair of electrodes formed on the surface of the piezoelectric ceramic.

According to one or more embodiments of the present invention, a mirrored apparatus includes a substrate with a non-metal inorganic material that is non-diamond turnable. The mirrored apparatus further includes a finish layer arranged on the surface of the substrate. The finish layer has a polished surface opposite the substrate. The mirrored apparatus also includes a reflective layer arranged on the polished surface of the finish layer.

According to one or more embodiments of the present invention, a mirrored apparatus includes a substrate with a non-metal inorganic material that is non-diamond turnable. The mirrored apparatus further includes a finish layer arranged on the surface of the substrate. The finish layer has a polished surface opposite the substrate. The mirrored apparatus also includes a reflective layer arranged on the polished surface of the finish layer.

Aspects of the disclosure provide methods of making a coated filtration material. Various methods include providing a base filter material and applying a first coating to the base filter material, the first coating being in nanoparticle form. A second coating is applied on top of the first coating, the second coating being a nanoscale inorganic material. The method further includes removing the first coating in such a way that the second coating remains on the base filter material. Methods of the disclosure can be used to manufacture coated filtration materials having a coating with a porosity of 90% or greater and a pore size in the range of 0.1-0.5 μm.

Aspects of the disclosure provide methods of making a coated filtration material. Various methods include providing a base filter material and applying a first coating to the base filter material, the first coating being in nanoparticle form. A second coating is applied on top of the first coating, the second coating being a nanoscale inorganic material. The method further includes removing the first coating in such a way that the second coating remains on the base filter material. Methods of the disclosure can be used to manufacture coated filtration materials having a coating with a porosity of 90% or greater and a pore size in the range of 0.1-0.5 μm.

A method of forming a ceramic-metal composite part is described herein. The method includes maintaining molten metal in an interior of a housing in a liquefied state, the interior including a first chamber, a second chamber, and a port defined therebetween. The method further includes sealing the port such that the molten metal in the first chamber is maintained at a first liquid level, suspending a part at a height within the first chamber above the first liquid level, forming a pressure differential between the first chamber and the second chamber, unsealing the port such that molten metal from the second chamber flows into the first chamber, and resealing the port when the molten metal in the first chamber reaches a second liquid level such that the ceramic part is submerged in the molten metal.

A method of forming a ceramic-metal composite part is described herein. The method includes maintaining molten metal in an interior of a housing in a liquefied state, the interior including a first chamber, a second chamber, and a port defined therebetween. The method further includes sealing the port such that the molten metal in the first chamber is maintained at a first liquid level, suspending a part at a height within the first chamber above the first liquid level, forming a pressure differential between the first chamber and the second chamber, unsealing the port such that molten metal from the second chamber flows into the first chamber, and resealing the port when the molten metal in the first chamber reaches a second liquid level such that the ceramic part is submerged in the molten metal.

A method of forming a ceramic-metal composite part is described herein. The method includes maintaining molten metal in an interior of a housing in a liquefied state, the interior including a first chamber, a second chamber, and a port defined therebetween. The method further includes sealing the port such that the molten metal in the first chamber is maintained at a first liquid level, suspending a part at a height within the first chamber above the first liquid level, forming a pressure differential between the first chamber and the second chamber, unsealing the port such that molten metal from the second chamber flows into the first chamber, and resealing the port when the molten metal in the first chamber reaches a second liquid level such that the ceramic part is submerged in the molten metal.

The present invention relates to a metalized ceramic substrate and a method for manufacturing the same. The method for manufacturing a metalized ceramic substrate of the present invention comprises the steps of: mixing copper powder and metal oxide to manufacture a copper paste; applying the copper paste to an upper surface of a ceramic substrate; and sintering the copper paste to form a copper metallization layer on the upper surface of the ceramic substrate. According to the present invention, it is possible to form, on the ceramic substrate, a thin copper metallization layer with high density, high bonding strength and low impurities.

A ceramic substrate includes a substrate main body, and a conductor layer provided inside of the substrate main body. The substrate main body includes an insulator layer that is ceramics composed of aluminum oxide, and a composite oxide layer of aluminum and silicon, the composite oxide layer being formed between the insulator layer and the conductor layer.