摘要
利用钛与 B4C,石墨之间的自蔓延高温合成反应经普通的熔铸工艺原位合成制备了等摩尔 Ti C和 Ti B增强的钛基复合材料。光学金相、EPMA、TEM和 X射线衍射的研究结果表明 :存在两种不同形状的增强体 ,即短纤维状 Ti B晶须和等轴、近似等轴状 Ti C粒子。增强体与 Ti基体界面洁净 ,没有明显的界面反应。由于增强体承受载荷 ,基体合金晶粒细化以及高密度位错的存在 ,制备钛基复合材料的机械性能有了较大的提高。石墨的加入导致形成更多的等轴、近似等轴状 Ti C粒子 ,有利于改善复合材料的性能。
TiB and TiC(TiB:TiC=1∶1) reinforced Ti matrix composites have been produced in situ using the self propagating high temperature synthesis(SHS) reaction of Ti with B 4C and graphite, common casting and hot forging technology. The experimental results show that there are two reinforcements with different shapes, short fibre TiB and equiaxed or near equiaxed TiC particles. TiB whiskers align along the hot forging direction. The interface between the reinforcements and the Ti matrix is clean. There is not interface reaction between the TiB and Ti matrix, while there are non stoichiometric annuli at the interface between the TiC and the Ti matrix. The mechanical properties of Ti matrix composites have been greatly improved for the following reasons: TiB whiskers and TiC particles undertake load, refinement of titanium matrix grains and produce a high density of dislocations in the Ti matrix. The graphite addition leads to the formation of more equiaxed or near equiaxed TiC particles, which are favourable for improving the mechanical properties of the composites.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2000年第3期153-157,共5页
Rare Metal Materials and Engineering
基金
国家自然科学基金重点资助项目!(596310 80 )
关键词
原位合成
钛基复
赤力学性能
石墨
微观结构
TiB
TiC
Ti matrix composite
in situ synthesis
mechanical property
