Dataset for Fatigue assessment of multilayer coatings using lock-in thermography

Dataset supports:
Laborda, A. et al. (2018). Fatigue assessment of multilayer coatings using lock-in thermography. Materials & Design.Plain bearings experience cyclic loading during operation, which may cause fatigue. In modern bearings a steel backing has a leaded bronze interlayer, covered by a thin (20 m) multi-layer coating, which consist of several electroplated layers composed by Sn, Ni and Cu. Commercial performance assessments simulate the conditions of an engine in a ‘Pass or Fail’ type of test. We propose a new methodology to assess the fundamental fatigue behaviour for such complex layered bearings. Accelerated fatigue tests on half-shell bearings have been conducted under 3-point bend in air, whilst the coated side of the bearings are recorded with an infrared camera. Cyclic tests with strain gauges placed on the coating have been performed to evaluate the strains developing during loading. By combining these tests we are able to rank different coatings. We also compare a compliance based failure criterion with a failure criterion based on early damage revealed by infrared thermography, showing that the latter is far less conservative. Thus, this methodology allow us to detect small scale fatigue cracks in the coatings, which facilitates assessment and identification of possible mechanisms that can explain the differences in fatigue performance between coatings. This provides valuable information for the development of new coatings for future bearing designs.