Lubricant Purposes Prevent metal-to-metal contact Remove or help dissipate heat Protect metal surfaces from corrosion Protect parts from contamination Any interposed substance that reduces friction and wear is a lubricant Lubricants are usually liquid but can be a solid,such as graphite,or a gas,such as pressurized air 6 Introduction to Engineering6 Introduction to Engineering Lubricant Purposes Prevent metal-to-metal contact Remove or help dissipate heat Protect metal surfaces from corrosion Protect parts from contamination Any interposed substance that reduces friction and wear is a lubricant Lubricants are usually liquid but can be a solid, such as graphite, or a gas, such as pressurized air