摘要
通过2TiC-Ti-1.2Al体系的原位热压反应制备Ti_3AlC_2陶瓷,然后以59.2Ti-30.8Al-10Ti_3AlC_2(质量分数,下同,%)为反应体系,采用放电等离子烧结技术制备Ti_2AlC/Ti Al基复合材料。借助XRD、SEM分析产物的相组成和微观结构,并测量其室温力学性能。结果表明:原位热压烧结产物由Ti_3AlC_2和TiC相组成,Ti_3AlC_2呈典型的层状结构,TiC颗粒分布在其间;SPS法制备的Ti_2AlC/Ti Al基复合材料主要由Ti Al、Ti_3Al和Ti_2AlC相组成,Ti_2AlC增强相主要分布于基体晶界处,发挥了晶界/晶内内生型强化相的增强作用。力学性能测试表明:Ti_2AlC/Ti Al基复合材料的密度、维氏硬度、断裂韧性和抗弯强度分别为3.85 g/cm^3、5.37 GPa、7.17 MPa·m^(1/2)和494.85 MPa,穿晶、沿晶及层状撕裂等混合断裂特征对改善性能发挥了重要作用。
Ti_3AlC_2 ceramics were fabricated by in-situ reaction in the 2TiC-Ti-1.2Al system.The Ti_2AlC/Ti Al composites were prepared by spark plasma sintering in the 59.2Ti-30.8Al-10Ti_3AlC_2(wt%)system.The phase composition and microstructure of the products were analyzed by XRD and SEM,respectively.The room temperature mechanical properties were also measured.The results reveal that the in-situ heat pressed Ti_3AlC_2 materials are composed of Ti_3AlC_2 and TiC phases.Ti_3AlC_2 ceramics present layered structure and TiC particles distribute around the grain boundaries.The Ti_2AlC/Ti Al composites prepared by SPS are mainly composed of Ti Al,Ti_3Al and Ti_2AlC phases.Ti_2AlC reinforcements are mainly distributed in the matrix grain boundaries,which exhibit the grain-boundary strengthening or intracrystalline strengthening effect.The density,Vickers hardness,fracture toughness and flexural strength of the Ti_2AlC/Ti Al composites are 3.85 g/cm^3,5.37 GPa,7.17 MPa·m^(1/2) and 494.85 MPa,respectively.The fracture features such as transgranular,intergranular and lamellar tearing play an important role in improving the performance of the composites.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2017年第S1期1-4,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金面上项目(51671116)
陕西省自然科学基础研究计划重点项目(2016JZ016)
陕西省教育厅自然科学重点科学研究计划项目(16JS018)
陕西省青年科技新星科技计划项目(2014KJXX-75)
陕西理工大学科研计划项目(SLGQD16-04)
