Abstract: A method includes obtaining multiple components to be coupled together, such as during a brazing operation. At least one of the multiple components includes a stop-off. The stop-off includes one or more markings formed on at least one surface of the at least one component. The one or more markings include (i) one or more etches in the at least one surface and/or (ii) one or more oxides formed by localized heating of the at least one surface. The method also includes coupling the multiple components together using a melted or liquid material, such as a filler metal used in the brazing operation. The stop-off controls or interrupts a flow of the melted or liquid material in a joint between the multiple components during the coupling. The one or more markings could interfere with a capillary action that pulls the melted or liquid material into the joint.

Abstract: A method includes obtaining multiple components to be coupled together, such as during a brazing operation. At least one of the multiple components includes a stop-off. The stop-off includes one or more markings formed on at least one surface of the at least one component. The one or more markings include (i) one or more etches in the at least one surface and/or (ii) one or more oxides formed by localized heating of the at least one surface. The method also includes coupling the multiple components together using a melted or liquid material, such as a filler metal used in the brazing operation. The stop-off controls or interrupts a flow of the melted or liquid material in a joint between the multiple components during the coupling. The one or more markings could interfere with a capillary action that pulls the melted or liquid material into the joint.

Abstract: A vehicle, such as a missile, is disclosed. The vehicle includes an optically transparent dome, a vehicle body, and a brazed joint directly coupling the dome to the vehicle body. The dome is formed of a Nanocomposite Optical Ceramic (NCOC) material comprising two or more different types of nanograins dispersed in one another. Each nanograin type has a coefficient of thermal expansion (CTE), and an aggregate CTE of the NCOC material is based on the CTE of each nanograin type.

Abstract: A vehicle, such as a missile, is disclosed. The vehicle includes an optically transparent dome, a vehicle body, and a brazed joint directly coupling the dome to the vehicle body. The dome is formed of a Nanocomposite Optical Ceramic (NCOC) material comprising two or more different types of nanograins dispersed in one another. Each nanograin type has a coefficient of thermal expansion (CTE), and an aggregate CTE of the NCOC material is based on the CTE of each nanograin type.

Abstract: A redundant sealing system includes a seal assembly for a vacuum or pressurized gas or liquid container, where the container has a fill port opening and a boss extending from a surface of the container. The boss has a passage aligned with the opening, and the passage has a threaded portion. The seal assembly includes a port plug having a nose portion with a surface shaped to mate with the fill port opening in the container and a set screw portion with external threads for engaging the threaded portion of the passage through the boss to press the nose portion into the fill port opening to form a first seal. The seal assembly further includes a weld plug sized to close the distal end of the passage through the boss, the weld plug is welded to the boss to form a second seal.