Abstract: A flux formulation for use in the assembly of electronic circuit boards having components to be joined by soldering. The formulation comprises a medium which acts as a carrier and solvent for the fluxing agent, which includes in a preferred embodiment supercritical carbon dioxide. The formulation also includes a fluxing agent, being at least partially soluble in the supercritical carbon dioxide which serves to transport the fluxing agent before deposition thereof upon a soldering site. The supercritical fluid is delivered through a nozzle to the circuit board, the supercritical condition being maintained until the supercritical fluid is discharged from the nozzle. The fluxing agent at least partially loses its solubility in the fluid thereupon and is transported to the board by a stream of carbon dioxide gas. Also disclosed is a method for delivering a flux formulation to the electronic circuit board.

Abstract: A nozzle expels liquid CO.sub.2 through an orifice for converting the liquid into CO.sub.2 snow. The nozzle is contained within an elongated cavity within a body which in turn is coupled to an exhaust nozzle for directing the CO.sub.2 snow toward a workpiece. A mixing device is provided for receiving and mixing pressurized air at ambient temperature with liquid nitrogen for precooling the air and then directing the resulting mixture of gases into the cavity and toward the nozzle. In this manner, the precooled shop air will enhance the efficiency of the conversion of the liquid CO.sub.2 into CO.sub.2 snow particles.

Abstract: A CO.sub.2 nozzle receives and expels liquid CO.sub.2 through orifices sized for converting the CO.sub.2 liquid into CO.sub.2 snow. A body, defining an elongated cavity therein, is coupled to the CO.sub.2 nozzle such that the CO.sub.2 snow is ejected into the cavity. An exhaust nozzle is coupled to the body and the cavity therein for directing the pressurized CO.sub.2 snow toward the workpiece. The exhaust nozzle is operated in an overexpanded mode for containing the shockwave within the nozzle for reducing the shear noise therefrom. Pressurized air is injected into the elongated cavity for exhausting the CO.sub.2 snow under pressure.

Abstract: A gas flow distribution system for a solder dispensing head includes a base member adapted to be connected to the solder dispensing head and a structure connected to a source of an inert gas for distributing at least one continuous stream of the inert gas radially and axially below the solder dispensing head to exclude oxygen in the surrounding air therefrom.

Abstract: An environmental wind tunnel facility for automotive vehicles, such as passenger cars, is provided with a slotted-wall extension which improves the air flow simulation over the entire vehicle and enables a reduction in the physical size of the environmental wind tunnel.