中文摘要：

采用放电等离子烧结和热处理工艺制备相对密度为99.6%的Ti4AlN3块体材料。用X射线衍射、扫描电子显微镜和能谱仪等分析测试手段研究Ti4AlN3的相形成及显微结构。结果表明：在900℃以下,Ti和Al反应生成金属间化合物TiAl3;在900～1200℃,TiAl3和TiN反应生成Ti2AlN;在1200～1300℃,TiN和Ti2AlN反应生成Ti4AlN3,延长保温时间有利于Ti4AlN3相形成;1300℃热处理4h可得到致密Ti4AlN3材料,且晶粒发育完全,为长约10～15μm、宽约2～5μm的板状晶;样品的Vichers硬度为2.7GPa,抗弯强度为350MPa,断裂韧性为6.2MPam1/2,常温电导率为4.7×105S/m。

英文摘要：

Bulk Ti4AlN3 with a relative bulk density of 99.6% was successfully fabricated by spark plasma sintering and annealing.Phase composition and microstructure of samples were characterized by X-ray diffraction,scanning electron microscopy analysis,and energy-dispersive spectroscopy.Results indicate that Ti reacts with Al to form intermetallic TiAl3 at 900 ℃;TiAl3 reacts with TiN to form Ti2AlN at 900–1 200 ℃.At 1 200–1 300 ℃,TiN reacts with Ti2AlN to form Ti4AlN3,and increasing holding time can promote the formation of Ti4AlN3 phase.Dense bulk sample of Ti4AlN3 was synthesized by annealing at 1 300 ℃ for 4 h.Grains were well developed with plate-like exposure,diameters of 2–5 μm,thicknesses of 10–15 μm,and elongated dimensions.Vickers hardness,fracture toughness,and flexural strengths of the bulk Ti4AlN3 are 2.7 GPa,350 MPa,and 6.2 MPa？m1/2,respectively.The electrical conductivity is 4.7 × 105 S/m.