摘要
用熔铸法制备了体积分数分别为8%和12%TiC的TiCP/Ti-6Al-4Sn-2Mo-0 2Si复合材料.通过SEM、TEM、XRD等手段研究复合材料的微观组织和断口形貌.TiC颗粒的加入使复合材料的铸态强度比基体有了大幅度的提高,但同时出现了含低体积分数增强相材料的强度和延伸率均比高体积分数材料高的现象,其原因主要来自于铸态下TiC形态的差异,后者组织中存在较多的枝晶状TiC,而前者组织中绝大多数TiC为细小颗圆整颗粒,有利于合金性能的提高.因此自生复合材料中增强相形态对性能影响,有时比体积分数更重要.
TiCp/Ti-6Al-4Sn-2Mo-02Si composites with 8%Vol and 12%Vol TiC were prepared by using melting casting processing. Microstructure and fracture morphologies were investigated by means of SEM, TEM, and XRD. The experimental results demonstrated that as cast strength of composites was significantly improved in comparison with the matrix' strength. However, the experimental results also indicated that the strength and ductility of composite with higher volume fraction of TiC are lower than that of composite having lower volume fraction TiC. This reason can be ascribed to the different morphologies of TiC. TiC particles in composite with lower volume fraction reinforcement are fine and smooth spheroid and are not dendritic as observed in composite with higher volume fractions of reinforcement, which contributes to the improvement of properties of composite. So, it can be concluded that sometimes the effects of morphology of reinforcement on properties of composites are more significant than the volume fraction of the reinforcements.
出处
《材料科学与工艺》
EI
CAS
CSCD
2003年第1期25-29,共5页
Materials Science and Technology
基金
金属精密热加工国防科技重点实验室开放基金项目99JS61.5.5.1.ZS6102.
