原位合成TiB2的定量计算及Cu-TiB2复合材料性能的研究

Quantitative analysis of TiB2 particles and properties ofCu- TiB2 composite prepared by in situ reaction

摘要:

以Ti粉、B粉和Cu粉为原材料,球磨后,采用原位热压法合成Cu-15wt%TiB₂复合材料。详细讨论了Cu-Ti-B体系的反应过程。通过XRD、SEM、EDS、XPS等手段,确定了Ti和B在Cu基体中原位合成了TiB₂,并利用XRD制作TiB₂和Cu的定标曲线,采用外标法计算出不同烧结温度下TiB₂的合成率,结果表明,在一定的温度范围内,温度越高,合成率越高,在1000℃时TiB₂的合成率可达99.27%。并测试Cu-1.5 wt%TiB₂块状试样的维氏硬度,电导率和三点弯曲强度,分别为125.68 MPa、80.1% IACS和755.2 MPa,在100℃时的热膨胀系数和导热系数分别为9.3×10_-6 /K和260 W/mK。

Abstract:

Cu-TiB₂ composites were prepared by combining in situ reaction and hot-pressing under different temperatures after ball-milling of the mixture powders of Cu, Ti and B. The reaction process of Cu-Ti-B system is discussed in detail. By means of XRD, SEM, EDS and XPS, it was determined that TiB₂ nano-particles generated by in situ reaction in Cu-matrix. According to making the calibration curve of TiB₂ and Cu by XRD, the concrete synthesis rate of TiB₂ in Cu-matrix under different sintering temperature by external standard method was confirmed. The experiments show that under certain temperature range, the higher the temperature is, the higher synthesis rate is, and the best synthesis rate of TiB₂ is 99.27% at 1000℃. Cu-1.5wt%TiB₂ prepared at 1000℃had the best properties, Vickers hardness(HV), electric conductivity(EC), flexure strength(FS), thermal expansivity(TE) and thermal conductivity(TC) at 100℃ were 125.68MPa, 80.1 % IACS, 755.2 MPa, 9.3×10_-6 / K and 260 W/mK, respectively.