Electrical and mechanical studies on pure-silver coated aluminium based electrical contact materials. (2020)

• Record Type: Journal Article
• Authors: Praveen Kumar, S.; Parameshwaran, R.; Arun Kumar, S.; Nathiya, S.; Heenalisha, K.
• Is Part Of: Materials today. Volume 33:Part 7(2020)
• Page Start: 3621
• Page End: 3625
• Publication Date: 2020
• Subjects: Electrical contact material -- silver-Aluminium -- Casting -- Sputtering -- Physical properties; Materials science -- Congresses -- Periodicals; 620.1
• DOI: 10.1016/j.matpr.2020.05.666
• Languages: English
• ISSNs: 2214-7853

Abstract

Abstract: Presently, the usage of electrical switches is widely increasing in industrial and house-hold applications. In switches, the electrical contact plays a foremost role in conducting electrical current between load and line. The electrical contact materials consists of alloys of pure copper (Cu), Silver – Cadmium Oxide (Ag–CdO) and Silver – Tin Oxide (Ag-SnO2 ) in different combinations that are usually fabricated by powder metallurgy processes. The major failures in current combinations occur due to thermal erosion of the contact point. This is due to the limitations in electrical conductivity and mechanical properties of the current combinations used. Pure silver possess highest electrical conductivity and good thermal stability. This present study aims in studying the electrical and mechanical properties of pure silver (Ag) coated over Aluminium (Al) based electrical contacts. Initially, pure Ag is extracted from the Silver nitrate (AgNO3 ) solution using colloidal synthesis process. The extracted pure silver is coated over casted Al contact material using Radio Frequency Magnetron (RFM) sputtering. The surface texture of Ag coated Al contact material is analyzed by scanning electron microscope (SEM). Further the Coated material is tested for mechanical and electrical properties based on ASTM standards. The casted and coated contact material has ahardness of HV 102.67 and electrical conductivity of 58.75 S/m. The values are at par with the properties of existing material combinations with improved thermal stability.