METHOD OF PERMANENT JOINTING OF POROUS, CELLULAR, FIBROUS MATERIALS WITH METALS AND ALLOYS Russian patent published in 1998 - IPC

FIELD: jointing of loose materials different in kind, for instance, in forming of electric lead contact zones of high quality and reliability. SUBSTANCE: the offered method includes jointing of porous, cellular, fibrous materials, placing on them of electric lead metal plates (electrodes), for instance, copper plates; submersion of sections to be jointed into electrolyzer. In this case, cathode is in form of current lead metal plate, and anode is in form of soluble electrode, and porous, cellular, fibrous material confined between them serves as the secondary cathode with variable electrical characteristics. In case of jointing of very loose materials with metals and alloys, porous, cellular, or fibrous material in zone of electric lead contact is threaded with current conducting material, for instance, copper wire, which serves as additional anode. In this case, current conducting material threading the porous, cellular or fibrous material may serve as cathode, and external strips serve as soluble anodes. In addition, placed between soluble anode and porous, cellular or fibrous material is thin drainage partition which varies density of ion flow and forming joint pattern. Electrodes may be made in form of plates with pinned surface where pins set up gradient electric field forming joint pattern. Besides, porous, cellular or fibrous material jointed with metals are arranged successively to form package and separated with insulating partition. In this case, cathode of preceding layer is electrically connected with anode of subsequent layer. In addition, soluble anode (extreme) in package is made in form of combined member with insulating spacer breaking electric circuit after dissolving of the preset part of anode. To reduce diffusion of metal ions to zones of porous cellular, fibrous materials adjacent to contact, the end face surfaces of electrodes are coated with adhesive compound ensuring preliminary fixing of electrodes. To enhance the quality of joint of porous, cellular or fibrous materials, electrolysis is carried out at superhigh densities of current of periodically varying polarity. EFFECT: higher efficiency. 9 cl, 8 dwg