摘  要本课题主要研究的是回火对钛基复合材料（TMCs）的组织及力学性能的影响。主要是对轧制后5 vol。% (TiC+TiB)/Ti-6Al-4V材料进行不同温度下的退火，以及在温度为1080℃条件下淬火后不同温度下的回火转变的研究。并且对TMCs进行不同温度等温转变。对热处理后TMCs试验，利用超景深显微观察，扫描电镜（SEM）研究多元增强体钛基复合材料的微观组织。利用X射线衍射（XRD）分析复合材料的相组成；利用显微硬度计了解Ti-6Al-4V不同热处理条件下的硬度变化；利用拉伸试验机测试热处理对TMCs力学性能的影响。从而初步了解不同回火热处理后钛基复合材料力学性能以及组织变化。得到的结论：随着退火温度的升高，对于5 vol。% (TiC+TiB)/Ti-6Al-4V钛基复合材料的基体晶粒变得粗大，在800℃温度以上退火时出现了大块的α相。这是因为退火时α相晶粒增长过大，晶粒生长到一起，使晶界难以区分，形成大块的α相。5 vol。% (TiC+TiB)/Ti-6Al-4V钛基复合材料淬火形成了针状的马氏体。回火使得马氏体的分解形成针状的α相。等温相变900℃比700℃的拉伸强度和延伸率都比较高，这是因为900℃出现等轴的α相，等轴α相的拉伸强度和延伸率比片状α相大。87088

毕业论文关键词： 钛基复合材料；热处理；相变

Abstract The topic of this object is researching the effect of tempering on the microstructure and mechanical properties of titanium-based composite materialt(TMCs)。The process of this issue is mainly  being annealed at different temperatures on rolled 5 vol。% (TiC + TiB) / Ti-6Al-4V material,and studying the conditions of different temperatures and tempering transformation after quenching at a temperature of 1080 ℃。5 vol。% (TiC + TiB) / Ti-6Al-4V material is directly tempered in different temperatures。Study the isothermal transformation of TMCs at different temperature 。Through these different heat treatment methods,we can use super-depth microscopic observation,and scanning electron microscopy (SEM) to study the  microstructure of heated TMCs 。 We can analyze the phase composition of the composite material in X-ray diffraction (XRD) 。Learning the use of micro hardness tester hardness change under the Ti-6Al-4V different heat treatment conditions to find a certain regularity;Using tensile testing machine to test heat treatment on the mechanical behavior of TMCs。Thus we can make a preliminary understanding of the different material mechanical heat treatment of titanium matrix composites performance and organizational change。Conclusion:With the tempering temperature, matrix grain of 5 vol。% (TiC + TiB) / Ti-6Al-4V titanium matrix composites becomes coarse and  chunks of α phase  appeared at temperatures above 800 ℃ tempered。This is because the grains grow too large and making it difficult to distinguish between grain boundaries when annealing,which forming chunks of α phase。5 vol。% (TiC + TiB) / Ti-6Al-4V titanium-based composite material formed needle α phase when  tempering。this is because the temperature quenching to form a needle-like martensite grain refinement。In the process of isothermal phase change,the sample at 900℃ is higher in the tensile strength and elongation than sample at 700℃,This is because the alpha phase appeared in the sample at 900℃,and axial tensile strength and elongation of alpha phase is larger than flake alpha。

Key words:Titanium matrix composites; Heat treatment; Phase transition

目 录

第一章 绪论 1

1。1引言： 1

1。2钛的合金相变 1

1。3钛合金热处理方法 2

1。3。1退火