TiBw对高温钛基复合材料基体的强化作用研究

Study on Strengthening Effect of TiBw on Matrix in High Temperature Titanium Matrix Composites

摘要:

以名义成分为Ti-6Al-4Sn-10Zr-1Mo-1Nb-1W-0.3Si的基体钛合金和3%(体积分数)TiBw增强高温钛基复合材料为研究对象，采用纳米压痕法对比分析了TiBw对基体的强化作用。结果表明：3%TiBw增强钛基复合材料基体的平均微区硬度为6.18 GPa，较无增强相的基体钛合金提升14.4%；通过分别对比不同厚度α层片处以及距离TiBw远近不同位置的硬度，发现TiBw增强高温钛基复合材料基体微区硬度的提升主要源于增强相TiBw引起的基体组织细化，以及靠近TiBw增强相区域的基体受压缩变形时易于受阻；添加TiBw后使得基体微观组织不均匀，导致硬度离散度较大。

Abstract:

The micro-zone hardness of titanium alloy matrix of Ti-6Al-4Sn-10Zr-1Mo-1Nb-1W-0.3Si and 3vol%TiBw reinforced high temperature titanium matrix composites were investigated by nano-indentation, respectively. The results show that the average hardness of titanium matrix composites is 6.18 GPa, which is higher than titanium alloy matrix by 14.4%. By comparing the hardness with different thickness of α lamellar and the hardness with different distances to the TiBw respectively, it is found that the TiBw reinforced high temperature titanium matrix composites present higher hardness than the titanium alloy matrix. The reason is that the matrix microstructure is refined by TiBw and the deformation of matrix near the TiBw is easy to be blocked. The hardness data show a large dispersion due to the inhomogeneous microstructure caused by the addition of TiBw.