Effect of rolling-texture intensity on fretting damage and subsurface deformation behavior in a high-strength titanium alloy

Abstract

Fretting damage is common in the high-strength titanium alloy fastener widely used in the aeronautic industry, leading to the failure of fastening fit or the initiation of crack. The titanium alloy fasteners often have typical preferred orientation characteristics (i.e., texture), and this is one of the important factors affecting its performance. However, the investigations on the mechanism of β rolling-texture intensity on fretting damage resistance and subsurface deformation are less addressed. Hence, fretting wear tests were carried out on samples with different rolling texture intensities. The results demonstrate that the samples with quite low (A-10 % sample) and quite high (D-70 % sample) rolling-texture intensity both exhibit excellent fretting wear resistance, but their mechanisms are completely different. Uniformly dispersed grain orientation renders the A-10 % sample with good recovery ability and a positive friction effect during wear. Low stress only concentrating at grain boundaries (GBs) weakens cracks’ initiation and propagation. The unique orientation-layered structure (OLS) leads to excellent recovery ability and a positive friction effect. Crack propagation is inhibited and only propagates along the OLS boundary without a connected trend. However, samples with moderate rolling texture intensity exhibit severe wear. Dislocations are restricted in local areas, so the poor recovery ability makes them have a negative friction effect. Crack propagation driving force continuously increases. Appropriate rolling texture intensity can reduce wear by three times. This study can provide information on the principle for designing fretting damage-resistant alloys.