Investigation on the effect of rotational speed on rolling wear and damage behaviors of wheel/rail materials

Wear and damage transitions of wheel and rail materials under various contact conditions

“…Fe-based alloy layer is composed of F (Fe, Ni) solid solution and Cr7C3 carbide and the surface hardness is about 670 HV0.5 [33]. Detailed information on the twin-disc machine and experimental approaches including the contact conditions (contact pressure, sliding speed, slip ratio, test duration, etc) can be found in previous publications [25,[30][31][32][33][34][35][36][37][38].…”

Experimental investigation on the effect of tangential force on wear and rolling contact fatigue behaviors of wheel material

“…As can be seen from Figs.3 and 9, the microstructure of wheel material is composed of ferrite and pearlite, and the soft ferrite phase shapes to a line because of the plastic deformation from mixed-mode loading (normal force, tangential force and lateral force). When repeated deformation eventually leads to the material reaching its plastic strain limit, a fatigue crack initiates and grows along with the soft ferrite line [23]. After a number of cycles the material above the fatigue crack fractures.…”

“…The lamellar structure cracks prevent the interlayer metal material and the contact surface of wheel/rail rollers from coming into direct contact. Therefore, the interlayer material under cyclic normal force is easy to be crushed [23].…”

“…With the tangential friction force increasing, the depth of the subsurface maximum shear stress decreases and the position of the subsurface maximum shear stress tend to be closer to the surface, leading to the thickness of wear debris shows a downtrend as shown Fig.13. During the rolling-sliding process, the surface of wheel/rail rollers can be locally heated and then rapidly cooled by the conduction into the bulk of the rollers [23,[25][26]. Therefore, the presence of Fe 2 O 3 and Fe 3 O 4 indicates that the material is oxidized to some extent when breaking off.…”

Effects of rail materials and axle loads on the wear behavior of wheel/rail steels

“…[1][2][3] As a consequence, a new impulse in the study of wear and failure mechanisms and new materials has been under investigation in recent years. [4][5][6][7][8] A major method in the development of new wheel/ rail materials, especially the rail steel, is to improve the wear resistance and rolling contact fatigue (RCF) resistance through higher hardness. 9 Increasing hardness is relatively easy to achieve by adding alloying element (mainly manganese and vanadium) and applying heat treatment.…”