This work presents a quantitative evaluation of the tribological performance of stereolithography (SLA)-processed alumina, addressing build orientation, contact-pressure effects, and wear-mechanism transitions under dry sliding. The sintered material achieved a density of 3.8-3.9 g cm -3 , grain size of 5.0 ± 0.8 μm, and Vickers hardness of 1759 HV, approaching conventional technical alumina despite residual porosity. Dry pin-on-disk tests (2-20 N) against steel, alumina, and tungsten carbide (WC) showed wear rates on the order of 10 -6 mm 3 N -1 m -1 for alumina-alumina and alumina-WC contacts, with mass losses below 2.0·10 -4 g. The steady-state coefficient of friction stabilized between 0.50 and 0.70 and was largely load-independent. In contrast, steel counterparts exhibited an average mass loss of 1.2·10 -2 g, demonstrating the strong abrasive capability of SLA alumina. Increasing build orientation roughness from Ra = 0.51 μm (x-y) to 1.61 μm (x-z) did not significantly affect steady-state wear, indicating isotropic tribological behavior. SEM analysis revealed a stress-driven transition from fatigue cracking at 2 N to compact protective tribolayers over 10 N, explaining the reduction in wear rate with load. Against metallic alloys, induced wear rates ranged from 10 -3 to 10 -6 mm 3 N -1 m -1 while alumina mass loss remained in 10 -4 g, supporting its suitability for severe dry-contact and potential cutting-tool applications. • SLA alumina shows minimal wear against steel, WC, and conventional alumina. • Print orientation of the SLA alumina has negligible influence on tribological behavior despite surface roughness differences. • Wear shifts from fatigue to tribofilm formation as load increases. • SLA alumina shows strong abrasive capability and cutting-tool potential.
Garcia-Hernandez et al. (Sun,) studied this question.