What is adhesive wear primarily characterized by?

Adhesive wear is primarily characterized by metal-to-metal contact leading to cold welding. This occurs when two metal surfaces come into contact under pressure, and the microscopic high points of the surfaces bond together. When these surfaces move against each other, material can be transferred from one surface to another, resulting in wear. The intensity of the metal-to-metal contact can cause localized melting at the contact points, which is often referred to as cold welding. This type of wear is distinct because it typically happens in the absence of contaminants or lubricants, making the direct contact between the metals crucial to the process.

While other options describe different types of wear mechanisms, adhesive wear specifically focuses on the interaction and bonding of metal surfaces under load, making the identification of this characteristic essential in understanding how adhesive wear operates in mechanical systems.