摘要
利用Al_3Ti/Ti N纳米复合粉体在1280℃/150 MPa/1 h热等静压条件下,制备出Al_2O_3/Ti_4Al N_3复合材料。利用XRD、SEM和TEM研究复合材料的形貌及成分。研究表明,复合材料主要由片层结构的Ti_4Al N_3基体和Al_2O_3颗粒增强相组成。Ti_4Al N_3基体的平均晶粒尺寸为7μm;Al_2O_3颗粒的弥散分布,形状不规则,粒度在1~3μm,体积分数约为27%。Al_2O_3/Ti_4Al N_3复合材料的强化机制为细晶强化和第二相粒子强化。Al_2O_3/Ti_4Al N_3复合材料与单相的Ti_4Al N_3材料相比,显微硬度从2.5GPa提高到6.7 GPa,室温下最大抗压缩强度从450 MPa提高到1 800 MPa,最大压缩应变由4%提高到6.2%。
Bulk intermetallic-ceramic composite Al_2O_3/Ti_4 AlN_3 was fabricated by in-situ hot isostatic pressing of Al_3Ti/Ti N nanopowders under the condition of 1280 ℃150 MPa/1 h.The microstructure of the composite was investigated by X-ray diffraction,SEM and TEM.Results reveal that matrix Ti_4 AlN_3 grains are strip-like and Al_2O_3 particles disperse in matrix uniformly with irregular shapes.The average grain size of Ti_4 AlN_3 is 7 μm.The size of Al_2O_3 particles is in the range of 1~3 μm,and the volume fraction is about 27%.The Vickers hardness of Al_2O_3/Ti_4 AlN_3 composite is 6.7 GPa,and the maximal compressed strength is 1800 MPa.Maximum compressive strain increases from 4% to 6.2%.The micro-hardness and compressed strength of Al_2O_3/Ti_4 AlN_3 composite are higher than those of single Ti_4 AlN_3 phase.The strengthening mechanisms of composite are fine grain strengthening and second phase strengthening.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2016年第7期1811-1815,共5页
Rare Metal Materials and Engineering
