Abstract: A new mold solves problems that arise from differential changes in geometry inherent to casting metal in a ceramic mold, by control of the internal morphology between the surfaces of the mold that face the casting, and that face the external environment. Layered fabrication techniques are used to create a ceramic mold. For example, an internal geometry composed of a cellular arrangement of voids may be created within the mold wall. Structures may be designed and fabricated so that the ceramic mold fails at an appropriate time during the solidification and/or cooling of the casting. Thus, the casting itself is not damaged. The mold fails to avoid rupture, or even distortion, of the casting.

Abstract: A new mold solves problems that arise from differential changes in geometry inherent to casting metal in a ceramic mold, by control of the internal morphology between the surfaces of the mold that face the casting, and that face the external environment. Layered fabrication techniques are used to create a ceramic mold. For example, an internal geometry composed of a cellular arrangement of voids may be created within the mold wall. Structures may be designed and fabricated so that the ceramic mold fails at an appropriate time during the solidification and/or cooling of the casting. Thus, the casting itself is not damaged. The mold fails to avoid rupture, or even distortion, of the casting. A thin shell of ceramic defines the casting cavity. This shell must be thin enough to fail due to the stresses induced (primarily compressive) by the metal next to it and partly adherent to it.

Abstract: A deposition resistant lining assembly is provided for a chemical vapor deposition chamber, the deposition resistant lining assembly including a first ceramic liner for mounting adjacent a substrate holder within the chemical vapor deposition chamber to protect a portion of an interior wall of the chemical vapor deposition chamber from deposition of material on the portion of said interior wall of the chemical vapor deposition chamber. The deposition resistant lining assembly also includes a second ceramic liner for mounting in a pumping channel formed in a peripheral region of the chemical vapor deposition chamber to protect a portion of said pumping channel from deposition of the material on the portion of the pumping channel. The first ceramic liner and the second ceramic liner are more resistant to deposition of the material than aluminum and easier and faster to clean of the material deposited thereon than aluminum.

Abstract: A throttle valve assembly is provided, including a throttle valve housing having a bore therethrough and a throttle valve plug assembly. The throttle valve plug assembly includes a shaft rotatably mounted on the throttle valve housing and a throttle valve plug having a concave cut-out portion. The throttle valve plug is mounted on the shaft within the throttle valve housing and substantially perpendicular to the bore. The throttle valve plug has at least two fully open positions and a closed position.