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Machine translation
1. (WO1981000644) SILVER,CADMIUM OXIDE,LITHIUM CARBONATE CONTACT MATERIAL AND METHOD OF MAKING THE MATERIAL
Latest bibliographic data on file with the International Bureau   

Pub. No.:    WO/1981/000644    International Application No.:    PCT/GB1980/000129
Publication Date: 05.03.1981 International Filing Date: 20.08.1980
IPC:
C22C 32/00 (2006.01), H01H 1/0237 (2006.01)
Applicants:
Inventors:
Priority Data:
68038 20.08.1979 US
Title (EN) SILVER,CADMIUM OXIDE,LITHIUM CARBONATE CONTACT MATERIAL AND METHOD OF MAKING THE MATERIAL
(FR) MATERIAU DE CONTACT COMPOSE D'ARGENT, D'OXYDE DE CADMIUM, DE CARBONATE DE LITHIUM, ET PROCEDE DE FABRICATION DU MATERIAU
Abstract: front page image
(EN)A material and a process for use in making electrical contacts. The material is produced in powder form suitable for later processing into electrical contacts by standard metallurgical techniques generally involving compacting the powdered material to form a compact that preferably has a backing of metallic silver, sintering the compact to form the contact having a fine sintered silver backing and forming or cutting the contact to make it to the desired shape and size. The material, and in most general applications the contact made from the material, essentially consists of silver, approximately 15% cadmium oxide by weight, and lithium carbonate at a proportion of about .005 weight percent of lithium, which is approximately equal to .04 molecular percent of lithium carbonate. The lithium carbonate is added to the powder mixture of silver and cadmium oxide powder mixture as a solution which is thoroughly mixed with the powders to form a slurry to uniformly distribute the lithium carbonate on the surfaces of the powder particles of cadmium oxide and silver by precipitation. The slurry in then dried and precipitated material is pulverized and formed into a compact without reducing the lithium carbonate prior to sintering of the compact. Thus by using lithium carbonate instead of lithium nitrate as known in the prior art, the step of reducing the lithium nitrate to lithium oxide prior to sintering the contact material is eliminated without sacrificing the performance of the contact material.
(FR)Materiau et procede utilise dans la fabrication de contacts electriques. Le materiau est produit sous forme de poudre appropriee pour etre transforme ulterieurement en contacts electriques a l'aide de techniques standard de metallurgie consistant en general a compacter le materiau en poudre pour former un comprime qui possede de preference une plaque de soutien d'argent metallique, le frittage du comprime pour former le contact ayant une plaque de soutien en argent finement fritte et la formation ou usinage du contact pour lui donner la dimension voulue. Le materiau, et dans la plupart des applications, le contact realise a partir du materiau est constitue essentiellement d'argent, approximativement de 15% d'oxyde de cadmium en poids, et de carbonate de lithium en une proportion d'environ 0,005% en poids de lithium, ce qui est approximativement egal a 0,004% en molecules de carbonate de lithium. Le carbonate de lithium est ajoute au melange pulverulent d'argent et de poudre d'oxyde de cadmium sous forme d'une solution qui est bien melangee aux poudres pour former une boue, de maniere a repartir uniformement le carbonate de lithium sur les surfaces des particules de poudre d'oxyde de cadmium et d'argent par precipitation. La boue est ensuite sechee et le materiau precipite est pulverise et forme en un comprime sans reduction du carbonate de lithium avant le frittage du comprime. Ainsi, en utilisant du carbonate de lithium plutot que le nitrate de lithium utilise dans l'art anterieur, l'etape de reduction du nitrate de lithium en oxide de lithium avant frittage du materiau comprime est eliminee sans pour autant reduire le rendement du materiau de contact.
Designated States:
Publication Language: English (EN)
Filing Language: English (EN)