Wear is one of the problems that occur in the moving parts either by rolling or sliding. This work includes experimental study on the wear of low carbon steel. Three surface treatments were chosen these are cyaniding, solid carburizing and hard chrome plating. The wear test was made under dry contact condition for the treated and the untreated surfaces. A constant load and speed were used for two types of motion: sliding-rolling and pure rolling. An Amsler machine was used. The high carbon steel was chosen for making the upper specimen and the low carbon steel was chosen for making the lower specimen. The high carbon steel was hardened while the other was surface treated (carburizing, cyaniding). The hard chrome plating was also used to increase the surface hardness. It was noticed that increasing of surface hardness reduced the wear amount produced, and the cyaniding gave the highest resistance to wear whereas the hard chrome plating gave the lowest one, and the wear under pure rolling condition was small .It was found that the wear rate of treated surfaces is high in the first stage of the test then the rate decreases until it reaches a steady state and for both motions.
Key Words: Wear, surfaceو treatment, hardening, steel.