【摘要】 为满足新一代航天器的轻量化需求，如何获得贮箱用原位自生Ti B₂/2219复合材料最优的热处理工艺参数组合，以进一步提升其综合力学性能，成为急需解决的重要问题。本文通过先进的表征技术和室温力学性能数据分析，系统研究固溶时效工艺对原位Ti B₂/2219复合材料力学性能的影响规律。结果表明：复合材料在535℃、1.5 h固溶条件下具有最高硬度，为108 HV；利用预拉伸使位错密度增加，为θ′相提供更多形核位点，提高了形核率，并增加时效过程中析出相的体积分数；设计中低温双级时效制度以促进原子团簇形成、增加析出相的形核位点，进一步提高θ′相的形核效率；在进行100℃×8 h和160℃×13 h时效后，屈服强度和抗拉强度相比未进行预拉伸的复合材料分别提高40.5%和12.5%，且仍保持8.0%的断裂应变。研究结果为我国航天贮箱用原位自生铝基复合材料的工程应用积累了有效的实验数据储备并提供技术支撑。更多还原

【Abstract】 To meet the lightweight requirements of the new generation of aerospace,obtaining the optimal heat treatment process parameter combination of in-situ Ti B₂/2219 composite for storage tanks to improve its comprehensive mechanical properties further has become an urgent problem.In this study,the effect of solution and ageing process on tensile properties of in-situ Ti B₂/2219 composite was systematically studied through advanced characterization techniques and analysis of tensile test data at room temperature was conducted.The results show that the compositehas the highest hardness of 108 HV at 535℃,1.5 h solution.Pre-stretch can increase the dislocation density,provide more nucleation sites for θ’phase,improve the nucleation rate,and increase the volume fraction of the precipitated phase during ageing.To promote the formation of atomic clusters,increase the nucleation site of the precipitated phase,and further improve the nucleation efficiency of θ’phase,a two-stage ageing system was designed.After ageing at 100℃×8 h and 160℃×13 h,the yield strength and tensile strength of the composite increased by 40.5%and 12.5%,respectively,while the fracture strain remained 8.0%.The results have accumulated effective experimental data and thus support the engineering application of in-situ aluminum matrix composites for space storage tanks.更多还原