摘要
In this work,bulk Zr_(3)Al_(3)C_(5)-based ceramics were synthesized by the infiltration of A1-Si melt into zirconium carbide (ZrC) perform.The phase composition,microstructure,and mechanical properties of as-fabricated ceramics were studied.The results demonstrate that Si is more effective to reduce the twin boundary energy of ZrC than A1,and thus promotes the decrease of formation temperature of Zr_(3)Al_(3)C_(5).With the infiltration temperatures increasing from 1200 to 1500 ℃,the Zr_(3)Al_(3)C_(5) content increases from 10 to 49 vol%,which is contributed to the increase of flexural strength from 62±9 to 222±10 MPa,and fracture toughness (KIC) from 2.8+0.2 to 4.1±0.3 MPa.m^(1/2).The decrease of mechanical properties for the samples fabricated at 1600 ℃ is ascribed to the abnormal growth of Zr_(3)Al_(3)C_(5) grains.
基金
This work was supported by the National Natural Science Foundation of China(Nos.51702261,52072303,and 51821091)
the Natural Science Foundation of Shaanxi Province(No.2019JQ-634)
the 111 Project(No.B08040)
the Fundamental Research Funds for the Central Universities.
