Abstract: A reaction bonded ceramic body that has 50% to 60%, by weight, boron carbide, and 20% to 30%, by weight, silicon carbide. The reaction bonded ceramic body has least a portion of the boron carbide reacted with silicon to become siliconized boron carbide. Also, a method of making a reaction bonded ceramic material. The method may include the steps of forming a green body from a mixture of boron carbide, carbon, and an organic binder, and contacting the green body with a liquid infiltrant comprising silicon. The infiltrant has a temperature of about 1625° C. to about 1700° C. Furthermore, a method of making a reaction bonded boron carbide ceramic body. The method includes the steps of forming a green body from a mixture of boron carbide, carbon, and an organic binder. The weight ratio of boron carbide to carbon in the green body may be about 5:5 to 1 or more.

Abstract: Embodiments relate to a coated substrate and a method of making and using the same. A plasma-spray coated layer may be formed on a substrate, wherein the plasma-sprayed coated layer comprises a rare-earth oxide (e.g., yttrium oxide), a rare-earth fluoride (e.g. yttrium fluoride), or a rare-earth silicate (e.g. yttrium silicate). An exposed surface of the plasma-spray coated layer may be irradiated to form a treated portion of the layer, wherein the treated portion of the layer has a mean spacing of local peaks (S value) between about 100 and 200 microns. A second layer may be formed on the treated portion of the plasma-spray coated layer, wherein the second layer comprises a dielectric material.