new definition ( no older found )
Galvanizing is the dipping of properly prepared steel into a molten tank of zinc metal. The molten zinc forms a metallurgical bond with the metal. As is the case with all zinc metal coatings, the zing acts as a galvanic coating, preferentially sacrificing itself at the anode
(Tom W. Neal, Maintenance Issues and Alternate Corrosion Protection Methods for Exposed Bridge Steel, p17)
2 - Burnishing
new definition ( no older found )
There is still a process that has been merely referred to but not described, and that is burnishing. A burnisher is a piece of hardened polished steel, and is applied by friction and pressure to the work, which must be very smooth. Burnishing is a method employed chiefly with metals on which a coat of superior metal, gold or silver, has been deposited electrically. An electro-deposited coat of silver of moderate thickness presents a dead white surface as it leaves the plating solution, unless this has been made to deposit bright silver by using a brightening solution. This surface is entirely devoid of lustre, and appears, when viewed through a powerful magnifying-glass, to be made up of a fine network of sliver grains cemented together. These grains absorb the light, and cause the deposit to assume a dull surface, known as "matt". It closely resembles frosted silver, and has a pleasing appearance when freshly deposited, rinsed in clean hot water, and quickly dried in a room free from dust. When this "matt" surface is scratch-brushed, it loses, to a certaşn extent, its peculiar dead whiteness, bu no amount of scratch-burnishing and polishing will give it the mirror-like surface so much desired in silver plate. To get a highly polished, reflecting surface on electro-plated goods, they are burnished after they have been well washed, scratch-brushed, and dried. Though the following instructions will have especial reference to the treatment of plated goods, they are also applicable to any metal work sufficiently soft to be affected by a hard burnisher.
(Paul N. Hasluck, Metalworking, chapter: polishing)
(strange book, no page numbers)
3 - Hot Swaging
new definition ( no older found )
Hot swaging is the initial manufacturing step in producing thin-diameter rods, which can then be further reduced in diameter by wire drawing. Through other contacts, a drop forging hammer was found a DFCLR, a German research center, which allowed extruding the preform at temperatures around 1500C. This produced a bar with enough strength to withstand the deformation during the subsequent swaging process. Now, the same porcesses of platinizing and carburizing were applied as in the initial sintered samples. The target to reach a lifetime of 10,000 hours, though, could not be reached.
(G. H. Gessinger, Materials and Innovative Product Development, p196)
3 - Hot Swaging
new definition ( no older found )
Hot swaging is the initial manufacturing step in producing thin-diameter rods, which can then be further reduced in diameter by wire drawing. Through other contacts, a drop forging hammer was found a DFCLR, a German research center, which allowed extruding the preform at temperatures around 1500C. This produced a bar with enough strength to withstand the deformation during the subsequent swaging process. Now, the same porcesses of platinizing and carburizing were applied as in the initial sintered samples. The target to reach a lifetime of 10,000 hours, though, could not be reached.
(G. H. Gessinger, Materials and Innovative Product Development, p196)
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