What effect does high temperature typically have on lubricants?

High temperature typically decreases the viscosity of lubricants. Viscosity is a measure of a fluid's resistance to flow; as the temperature of a lubricant rises, its molecules gain energy and move more freely, resulting in a thinner fluid. This decrease in viscosity can affect how well the lubricant can maintain a protective film between moving parts. At high temperatures, if the viscosity becomes too low, it may not provide adequate lubrication, potentially leading to increased friction, wear, and even failure of the machinery. Understanding the impact of temperature on lubricant viscosity is crucial for ensuring optimal performance and reliability in machinery operations.