NiAl-TiC原位复合材料的室温韧化机制研究

Study on the Room Toughening Mechanism in the Ni Al- Ti C in Situ Composite

通过热压放热反应合成 (HPES)工艺制备的 Ni Al- 2 0 vol% Ti C原位复合材料 ,它的平均室温断裂韧性值比单相 Ni Al提高了 5 0 % ,断口形貌及裂纹扩展路径观查表明 ,裂纹偏转机制是复合材料的主要韧化机制。

Fracture toughness of Ni Al- Ti C in situ composites was measured using single-edge notched three- point bend specimens. The composites were fabricated by a hot pressing aidedexothermic synthesis( HPES) technique.The results show that the average fracture toughness ofthe composite was8.9MPa.m1/2 ,50 % higher than that of monolithic Ni Al.From fracture sur-face and crack propagation path analysis,crack deflection was rationalized as the predominanttoughening mechanisms.