摘要:
A composite griddle plate is provided having a heavy copper core which is diffusion bonded to one or more outer plates of stainless steel, carbon steel or titanium. The copper cored composite is made by explosion bonding the outer metal plates to the copper core to achieve diffusion bonding followed by multi-pass, small, incremental reduction passes in a hot rolling mill conducted within a narrowly controlled temperature range falling within the overlapping hot working range of the copper core and the dissimilar metal of the outer layers.
摘要:
A method of producing an aperture extending from an optically flat surface through a substrate defining the optically flat surface to a surface of the substrate remote from the optically flat surface comprising the steps of: a) forming the optically flat surface; b) etching to form the remote surface to produce an area of the substrate of a desired thinness bounded by the optically flat surface; and c) laser cutting through the area of desired thinness from the remote surface toward the optically flat surface to produce aperture, of a desired shape and size; and a structure when made by the method.
摘要:
The output of a continuously pumped, Q-switched, Nd:YAG laser (10) is frequency converted to provide ultraviolet light (62) for plating internal wall surfaces (79, 126) of vias (72, 74) in multilayered electronic devices (80). The parameters of the output pulses (62) are selected to facilitate substantially uniform deposition of plating material particles explosively vaporized from a substrate (124) onto the internal wall surface (79, 126). These parameters typically include at least two of the following criteria: high average power of greater than about 100 milliwatts measured over the beam spot area, a temporal pulse width shorter than about 100 nanoseconds, a spot diameter of less than about 50 microns, and a repetition rate of greater than about one kilohertz.
摘要:
A method of welding using a high energy density radiation beam such as an electron beam or preferably a laser beam to weld a pair of sheets using an oblong focused beam spot for reducing the power density of the oblong beam spot to maximize welding speed while minimizing welding defects. The high energy density radiation beam source has a power of at least one kilowatt for achieving Keyhole welding, and a beam delivery system capable of focusing the beam into an oblong spot shape, such as a generally rectangular focused beam spot shape, and directing the beam spot onto at least one of the sheets to weld the sheets. During welding, the beam is focused into an oblong focused beam spot and trained on at least one of the sheets to weld them with the longitudinal axis of the beam spot preferably oriented generally tangent to the weld line, generally parallel to the weld direction, or acutely angled relative to the tangent to the welding direction. Preferably, if a laser is used, it is a laser emitting a continuous wave beam, a pulsed laser operating at a duty cycle of at least 50% such that it substantially performs as a laser emitting a continuous wave beam, or a laser in rippled or modulated mode having a continuous beam component with an average output power of at least 80% of the peak power of the laser so that it substantially performs as a continuous wave laser beam.
摘要:
A heavily thermally stressable component comprising a graphite and a metal part, e.g., copper or a copper alloy, soldered together. Between the solder and the metal part there is an intermediate layer comprising chromium or an alloy containing a substantial proportion of chromium with copper and/or nickel additives. This special intermediate layer provides a good bond between the graphite and the metal which remains stable even under the heaviest cyclic thermal stresses.
摘要:
A metallurgical joint between a copper tube and an aluminum tube is disclosed. The metallurgical joint between the tubes is elongated and extends along the length of the telescoping tubes and is substantially free of materials other than copper and aluminum. A method and apparatus for making the metallurgical joint is disclosed.
摘要:
At least one laser beam is focused on one side of an assembly to be cut at a point on the side which is part of the cutting profile and which is called the point of impact of the beam on side side, in order to cause at that point a disintegration of the material of the assembly. The laser beam is moved in relation to the assembly so that the impact point describes a trajectory which corresponds to the desired cutting profile, while maintaining a controlled atmosphere in the area around the impact point. Uses particularly include cutting solid polymer electrolyte lithium thin film electrochemical generators, or cutting precursors of such generators.
摘要:
A flexible automated bonding apparatus electrically interconnects integrated circuit carriers, printed circuit boards, and other devices. A metallized interconnect pattern is deposited on the surface of the substrate. The metallized interconnects in the pattern span apertures created in the substrate using an excimer laser. Thus, the metallized interconnects can be electrically bonded through the apertures to elements lying underneath the substrate.
摘要:
Conductive patterns may be formed on the surface of thermally inefficient substrates by depositing a uniform layer of metal thereover whose upper surface is substantially UV light absorbing followed by laser ablation of the deposited metal to leave the deposited metal only in the desired metal pattern. Thermally efficient substrates may be rendered thermally inefficient by the deposition of a thermally inefficient material thereon. That thermally inefficient material may be either electrically insulating or a metal. A two layer metallization comprising a first, thermally inefficient reactive metal and a second UV light absorbing metal is preferred. When disposed on a thermally inefficient substrate, this two layer metallization ablates reactively as the two layers burn off together. This laser ablation process substantially roughens the surface of polymer dielectrics and may be used to repair open traces in printed circuit structures.
摘要:
A method of ablating fluoropolymer composite materials is presented wherein it has been found that small holes (less than 100 .mu.m) can be formed in fluoropolymer composite laminate materials using UV lasers. The resulting holes can be used to produce vias and plated through-holes having smooth side walls with little or no debris or residue remaining in the holes and minimal damage to the polymer. Thus, the vias and plated through-holes can be plated without further cleaning processes. In addition, the holes are formed at a relatively fast rate.