Bending fretting fatigue damages of 316L austenitic stainless steel plates against 52100 steel cylinders

摘要

The bending fretting fatigue tests of 316L austenitic stainless steel plates with rectangular geometry against 52100 steel cylinders have been carried out under the same normal load and varied bending loads. The bending fretting fatigue morphologies and damages were analyzed by scanning electron microscopy equipped with energy dispersive X-ray spectrum, and the profiles of wear scars were measured by Ambiostechnology XP-2 profilometer. The S-N curves of the bending fretting fatigue were plotted. Results showed that the fatigue cracks appeared at the surface of the plate specimen. With the increase of the cyclical bending load, the depth of wear scar distinctly increased at the same cycle, and the fretting fatigue life dramatically decreased. With increasing the number of cycles, the width and the depth of fretting damage region enlarged. The wear mechanisms in the fretting damage zones were mainly abrasive wear, oxidative wear and de-lamination. The influence of bending load on the depth of fretting damage was higher than that of fretting contact load. The life of the sample decreased when the normal load on the fretting pad increased. The finite element analyses displayed that the cracks would initiate at the contact edge which inclined to the end of bending load, which agreed well with experiment results.