Abstract: A wave solder apparatus. A conveyer carries a circuit board. A solder tank is disposed under the conveyer and includes a turbulent nozzle and a laminar nozzle separated therefrom by a predetermined distance. A first heater is disposed under the conveyer and adjacent to the solder tank, heating the bottom surface of the circuit board. A second heater is disposed above the conveyer and opposes the first heater, heating the top surface of the circuit board. A third heater is disposed above the conveyer and opposes the turbulent and laminar nozzles of the solder tank, heating the top surface of the circuit board.

Abstract: A wave solder apparatus. A conveyer carries a circuit board. A solder tank is disposed under the conveyer and includes a turbulent nozzle and a laminar nozzle separated therefrom. The turbulent nozzle includes a plurality of turbulent spouting holes. The ratio of the cross-sectional area of the turbulent spouting holes to that of the turbulent nozzle exceeds 0.377. A first heater is disposed under the conveyer and adjacent to the solder tank, heating the bottom surface of the circuit board. A second heater is disposed above the conveyer and opposes the first heater, heating the top surface of the circuit board.

Abstract: A lead-free solder reworking method. A solder tank including a nozzle and containing molten lead-free solder is provided. A printed circuit board assembly is placed on the solder tank. The printed circuit board assembly has a printed circuit board and a first electronic member. The printed circuit board has at least one through hole. The first electronic member has at least one first pin soldered in the through hole by lead-free solder. The through hole and first pin are located above the nozzle. A reworking temperature and a reworking time are established. The printed circuit board is heated until the temperature thereof reaches the reworking temperature. The nozzle outputs the molten lead-free solder from the solder tank to the through hole of the printed circuit board until the nozzle operates for the reworking time.

Abstract: The present invention employs a mechanical mixture of titanium dioxide and calcium oxide which is sintered and ground to produce a ceramic powder for application to a target of an X-ray tube. The powder is fused by baking the target at a predetermined baking temperature to produce a coating having an enhanced coefficient of emissivity. The required baking temperature is controllable by varying the proportion of titanium dioxide to calcium oxide. Baking time may be extended without degrading the coating by mechanically mixing zirconium dioxide to the sintered and ground ceramic powder prior to application to the X-ray target in order to enhance outgassing from the target substrate. The resulting coating on the target improves the emissivity thereof and exhibits and improved bond strength over coatings of the prior art.

Abstract: An x-ray tube target composed of a molybdenum alloy material such as TZM is coated with a mixture containing from 40 percent to 70 percent of TiO.sub.2 with the remaining material being a stabilized oxide. The coating is then fused to a smooth, glossy condition to provide an enhanced thermal-emittance surface that adheres well to the target substrate.