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The cure package consists of various reagents that modify the kinetics and chemistry of crosslinking. These include accelerants, activators, retarders and inhibitors. [ 7 ] [ 8 ] Note that these are merely the additives used for vulcanization and that other compounds may also be added to the rubber, such as fillers , tackifiers , polymer ...
Lead frame for a QFP package, before encapsulation DIP 16 pin Lead frame, after encapsulation and before cutting/separation. The lead frame consists of a central die pad, where the die is placed, surrounded by leads, metal conductors leading away from the die to the outside world. The end of each lead closest to the die ends in a bond pad.
Leaded chip carriers have metal leads wrapped around the edge of the package, in the shape of a letter J. Leadless chip carriers have metal pads on the edges. Chip carrier packages may be made of ceramic or plastic and are usually secured to a printed circuit board by soldering, though sockets can be used for testing.
Mill finish is the surface texture (or finish) of metal after it exits a rolling mill, extrusion die, or drawing processes, including sheet, bar, plate, or structural shapes. This texture is usually rough and lacks lustre; it may have spots of oxidation or contamination with mill oil.
A #7 finish is produced by polishing with a 280–320 grit belt or wheel and sisal buffing with a cut and color compound. This is a semi-bright finish that will still have some polishing lines but they will be very dull. Carbon steel and iron are commonly polished to a #7 finish before chrome plating.
The integrated circuit package must resist physical breakage, keep out moisture, and also provide effective heat dissipation from the chip. Moreover, for RF applications, the package is commonly required to shield electromagnetic interference, that may either degrade the circuit performance or adversely affect neighboring circuits.
Mass finishing is a group of manufacturing processes that allow large quantities of parts to be simultaneously finished. The goal of this type of finishing is to burnish , deburr , clean, radius, de-flash , descale , remove rust , polish, brighten, surface harden , prepare parts for further finishing, or break off die cast runners.
Superfinishing, also known as microfinishing [1] and short-stroke honing, is a metalworking process that improves surface finish and workpiece geometry. This is achieved by removing just the thin amorphous surface layer of fragmented or smeared metal left by the last process with an abrasive stone or tape; this layer is usually about 1 μm in magnitude.