3D characterization of rolling contact fatigue crack networks

Analysis of Surface Crack Growth under Rolling Contact Fatigue

Understanding the fatigue crack growth phenomenon in railheads requires a study of driving forces such as the crack tip opening and sliding displacements, under repeated rolling contact. Finite element simulations, allowing elastic-plastic deformation, and mixed-mode crack growth laws were utilized to demonstrate that the fatigue crack growth rates display a minimum after a finite amount of cra...

Investigations of White Etching Crack (WEC) Formation under Rolling Contact Fatigue

A premature failure mode in steel rolling element bearings called white structure flaking (WSF) occurs in wind turbine gearbox bearings. WSF can occur in as little as 6-24 months of operation. WSF is associated with microstructural alterations called white etching area (WEA) and white etching cracks (WECs) that form in the ~1 mm zone beneath the contact surface. The tribological drivers for WSF...

Rolling contact fatigue in martensitic 100Cr6: subsurface hardening and crack formation

Rolling contact fatigue tests on 100Cr6 steel were carried out with a ballon-rod tester. Microstructural damage was manifested by gradual hardness changes under the subsurface, and microcracks formed adjacent to inclusions; both being evidence of plastic deformation. The hardness increase appears to be due to the development of residual stress, while the microcracks form as a result of the conc...

Rolling Contact Fatigue in Ultra High Vacuum

Fretting Fatigue with Cylindrical-On-Flat Contact: Crack Nucleation, Crack Path and Fatigue Life

Fretting fatigue experiments and finite element analysis were carried out to investigate the influence of cylindrical-on-flat contact on crack nucleation, crack path and fatigue life of medium-carbon steel. The location of crack nucleation was predicted using the maximum shear stress range criterion and the maximum relative slip amplitude criterion. The prediction using the maximum relative sli...