Electroerosion of electric contacts

• Published in: Вестник Научно-исследовательского института железнодорожного транспорта
• Main Author: V. Y. Berent
• Format: Article
• Language: Russian
• Published: Joint Stock Company «Railway Scientific and Research Institute» 2016-04-01
• Subjects: electric erosion; electric arc; contacts of matrix type; arc of matrix type; contacts of frame type; coal inserts; metal-carbon inserts; powder contact plates; high-melting component of contact composite
• Online Access: https://www.journal-vniizht.ru/jour/article/view/81
• ISSN: 2223-9731; 2713-2560

Contact wire of electrified railways and current collecting elements of strips of current collectors are working under atmospheric conditions, often causing failure of its interaction. Electrical discharges occur as a result of failure of the direct interaction between the contacts. Erosion of electric contacts occurs as a result of such discharges. Matrix type contacts, recommendations on its composition as well as nature of its damageability were considered. Destructions of carbon materials by arc discharge were investigated. Higher erosion resistance to metal-carbon inserts is shown. Positive role of low-melting phase in composition of frame-type contacts under the influence of an electric arc are confirmed. The erosion damages to the contacts during current collecting of high-density currents were considered. It is concluded that the construction of the contacts of frame type with a carbon matrix comes down to putting into it low-melting phase in the form of copper or its alloys by impregnation technology. Creation of contacts of frame type on a metal basis is carried out by input fusible metal into a framework of more high-melting metal through a charge of a powder composite or by technology of impregnation of already sintered material.