Lubrication of electrical contacts

The paper presents a review of research data published during last 40-year period in the field of electrical contact lubrication. The paper examines the role of lubrication in corrosion protection as a barrier between contact surfaces and atmospheric pollutants. For effective long-term corrosion protection, it is important to properly choose and thoroughly qualify a lubrication product for a specific contact material and a specific combination of environmental variables. Another use of lubricants is to protect contacts from mechanical wear and/or friction, and from degradation due to fretting. Conversely, use of inappropriate lubricants may induce a significant risk by producing degradation, collecting participate matter, and developing a high electrical resistance of the contact surfaces. It is very important to carefully choose the lubricants to maintain a stable contact resistance and preserve the physical integrity of the contact surface. This paper also analyzes the effect of chemical composition and consistency (fluids, greases, solid lubricants) on the durability of lubricants in regards to various types of contact material, design and load.