Abstract: A filler component for making an investment casting slurry, which comprises: a major portion of finely divided silica, aluminum silicate, alumina, zircon, or mixtures thereof; and a minor portion of one or more finely divided materials having particles in which, on average, at least one dimension of the particle is at least about four times greater than at least one other dimension of the particle. Typically, the particles are of generally plate-like or needle-like shape.

Abstract: A method of improving the removal of an investment casting shell surrounding a metallic article. The shell is made from the deposit of layers refractory slurry and stucco onto a pattern. The shell contains, after firing, an amount of an alkali metal oxide or an alkaline earth metal oxide sufficient to reduce the strength of the shell. By this invention, after firing of the shell and pouring of the molten metallic part into the shell, the shell is hydrated to further reduce the strength of the shell, to facilitate its removal from the metallic part.

Abstract: A method of improving the removal of an investment casting shell surrounding a metallic article. The shell is made from the deposit of layers refractory slurry and stucco onto a pattern. The shell contains, after firing, an amount of an alkali metal oxide or an alkaline earth metal oxide sufficient to reduce the strength of the shell. By this invention, after firing of the shell and pouring of the molten metallic part into the shell, the shell is hydrated to further reduce the strength of the shell, to facilitate its removal from the metallic part.

Abstract: A filler component for making an investment casting slurry, which comprises: a major portion of finely divided silica, aluminum silicate, alumina, zircon, or mixtures thereof; and a minor portion of one or more finely divided materials having particles in which, on average, at least one dimension of the particle is at least about four times greater than at least one other dimension of the particle. Typically, the particles are of generally plate-like or needle-like shape.

Abstract: A metal alloy, such as steel, is manufactured in an electric arc furnace system equipped with at least one sensor, at least one a controller including a logic program and a variable valve in fluid communication with the furnace and a material source. The nature and quality of the slag formed over a molten metal during manufacture of steel is dynamically controlled by continuously adjusting the addition of one or more material to the arc furnace through the variable valve.

Abstract: A metal alloy, such as steel, is manufactured in an electric arc furnace system equipped with at least one sensor, at least one a controller comprising a logic program and a variable valve in fluid communication with the furnace and a material source. The nature and quality of the slag formed over a molten metal during the manufacture of steel is dynamically controlled by continuously adjusting the addition of one or more material to the arc furnace through the variable valve.