研究目的
To develop a facile strategy for depositing an in-situ ceramic layer on the surface of Mo-based composites via laser powder bed fusion (L-PBF) to improve their oxidation resistance for ultrahigh-temperature applications.
研究成果
A thin ceramic layer was successfully formed on the surface of Al2O3-TiC/MoTiAl composite builds via L-PBF processing of Al2O3-CNT/MoTiAl mixed powders. The ceramic layer's thickness could be controlled by adjusting the number of powder stacking layers or the concentration of Al2O3 in the initial powders. The increased nanohardness of the alloy is attributed to the presence of uniformly dispersed, intimately contacted ceramic nanoparticles in its matrix. This study demonstrates the potential of L-PBF as a novel approach to fabricate advanced MMCs.
研究不足
The study mentions the intrinsic brittleness of Mo-based alloys and the possible high residual thermal stress arising from the rapid cooling of L-PBF, which could lead to internal microcracks. The thickness of the ceramic layer became saturated once it exceeded approximately 11 μm, the reason for which is unknown and requires further investigation.
