In situ synthesized (ZrB2+ZrC) hybrid short fibers reinforced Zr matrix composites for nuclear applications

Abstract In the present work, novel zirconium matrix composites reinforced with ZrB2 or (ZrB2 + ZrC) hybrid short fibers were designed and prepared for the first time, through the reaction from Zr, B and B4C with non-consumable vacuum arc melting. The result shows that the ZrB2 particles grow in large short-fiber shape while the ZrC particles grow in thin short-fiber shape or near equiaxed shape. The morphological characters are related to their crystal structure and growth mechanism. Homogeneous distribution of both two in situ reinforcements can be found in the as-cast composites. As both the Zr matrix and the in situ reinforcements have good nuclear and mechanical properties, these Zr matrix composites are considered to be good candidates for applied as reactor core components.