Abstract: An isogrid structure formed from multiple face sheets (14) and multiple stringers (16). Each face sheet (14) and each stringer (16) being an individual component. Each stringer (16) having two or more joints for attachment to the face sheets (14). The face sheets (14) formed from flat sheet material and include a pattern of openings for attachment of the joints on the stringers (16). The geometry of the openings matching the geometry of the joints on the stringers (16). The assembled unit is formed by inserting each joint on a stringer (16) through its corresponding opening in a face sheet (14) and then bonding the joint to the face sheet (14).

Abstract: The Boiler Automated Welding System (BAWS) is an automatic welding system for repair of worn boiler tubes in cyclone boilers. Repair of these tubes is essential for extending the life of this component used within electrical power plants. The BAWS utilizes: 1) a multiaxis positioner which forms the required cylindrical coordinate motion system, 2) a tube tracking systems for determination of motion paths during welding, 3) a two axis gimbaled welding torch holder for orientation of the welds relative to the motion path, 4) an integrated welding system and 5) a computer controller which coordinates these devices in a logical method. The BAWS multiaxis positioner allows for orientation of the system within the cyclone boiler to take advantage of the symmetry of the tube layout (cylindrical coordinates). The positioner allows each individual tube to be scanned and a weld path determined using a laser scanning device.

Abstract: A process for optimizing grain refining response of intermetallic TiAl.sub.3 or ZrAl.sub.3 in aluminum welding consumables comprising the steps of processing the intermetallic particles to first form a flake morphology in a master alloy solid, then as a component of the production of an ingot from an aluminum melt, to thermally fracture the flakes, then obtain dissolution of the interface material to increase distribution of the fractured particles and then, by mechanical working, to further fracture and distribute the intermetallic particles. The process is continued during the welding operation by using specific welding parameters during the welding with the consumable such that the intermetallic particles can withstand the weld pool environment in order that they maintain the characteristics and properties which will result in the creation of a small grain size in the weldment.