论文部分内容阅读
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900～1 200℃,TiAl3和TiN反应生成Ti2AlN;在1 200～1 300℃,TiN和Ti2AlN反应生成Ti4AlN3,延长保温时间有利于Ti4AlN3相形成;1 300℃热处理4 h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2.7 GPa,抗弯强度为350 MPa,断裂韧性为6.2 MPa·m1/2,常温电导率为4.7×105 S/m。
The Ti4AlN3 bulk material with a relative density of 99.6% was prepared by spark plasma sintering and heat treatment. The formation and microstructure of Ti4AlN3 were studied by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The results show that TiAl reacts with Ti and Al to form TiAl3 at 900 ℃, Ti2AlN reacts with TiN at 900 ~ 1200 ℃, Ti4AlN3 reacts with TiN and Ti2AlN at 1200 ~ 1300 ℃, prolongs holding time Ti4AlN3 phase is favorable for the formation of Ti4AlN3 phase. The dense Ti4AlN3 material can be obtained by heat treatment at 300 ℃ for 4 h, and the crystal grains are completely developed. The Vicat hardness is 2.7 GPa and the average crystal length is about 10 ~ 15μm and the width is about 2 ~ 5μm. The flexural strength is 350 MPa, the fracture toughness is 6.2 MPa · m1 / 2, and the room temperature conductivity is 4.7 × 105 S / m.