1. Adhesive wear
When the friction pair moves relative to each other, the phenomenon that the material of the contact surface is transferred from one surface to another due to solid phase welding is called adhesive wear. When there is no lubricating oil between the friction pairs, or the oil film between them is broken due to excessive load, adhesive wear is particularly prone to occur. In severe cases, the friction pair will bite; it is also called bite wear
Gear adhesive wear
The characteristics of the metal surface are: a very thin transfer film is often adhered to the metal surface with chemical composition changes;
2. Abrasive wear.
The phenomenon of surface material falling off caused by the cutting or scraping of hard objects or particles. Abrasive wear can be divided into three forms: chiseling, high stress crushing and low stress abrasion. Since the hard object or particle may be an intermediate material, or the friction pair itself, the cutting or scraping action can occur in a single friction stroke, so the wear amount is often very high, which is most common in industry. About 50% of mechanical parts are damaged due to abrasive wear.
Abrasive wear
Morphological characteristics of abrasive wear: grooves formed by obvious plowing on the friction surface;
3. Surface fatigue wear
When two contact surfaces are subjected to rolling or rolling-sliding composite friction, the material surface fatigues under the action of alternating contact pressure stress and produces material loss. Gear pairs, cam pairs, rolling bearings, rails and wheel hoops can all produce surface fatigue wear. Since the magnitude of contact pressure stress changes with time or position, surface fatigue wear is accompanied in many wear processes.
Morphological characteristics: manifested as the gradual formation and expansion of cracks, the shedding of surface particles, and the leaving of pits and holes.
4. Corrosion wear.
During the friction process, the metal reacts chemically or electrochemically with the surrounding medium at the same time, resulting in material loss. Due to the nature of the medium, the state of the medium acting on the friction surface, and the different properties of the friction material, the state of corrosion wear is also different.
Morphological characteristics: surface erosion pits (fish scales) and short-range groove deformation layers have tiny cracks.
Steel Pipe
