Cyclic indentation analysis of PC/ABS blends: Effects of fatigue and fatigue combined with torsional fretting wear

Previous works have shown that PC/ABS blends can be good candidates for wear-resistant coatings under monotonic loading. However, research is lacking on their response to fatigue and fatigue combined with torsional loads. This study investigates four PC/ABS configurations (100:0, 80:20, 65:35, 0:100) under cyclic indentation load and oscillatory torsional load for various numbers of cycles. PC/ABS 65:35 is found to be the least resistant, being the only material to fracture due to fatigue. However, the addition of an angular displacement postponed the onset of structural failure in the 65:35 blend, increasing its life by approximately 20%. Remarkably, the same multi-axial loading suppressed fracture entirely in the 80:20 and 0:100 configurations while producing only small non-propagated cracks in the 100:0. These findings provide evidence that superimposed torsional fretting can actively retard compressive-fatigue damage in thermoplastic polymers and open a novel route for the customization of protective coatings for complex loads.