摘要
以Al和TiO2为初始原料,经高能球磨及热压烧结工艺,原位合成了TiN/Al2O3复合材料。利用DTA,XRD及SEM等方法结合热力学计算,研究了该粉体的高能球磨过程和球磨粉体在后续热处理中的物相形成及转化规律。同时研究了以高能球磨及热压烧结工艺所制备的复合材料的力学性能和显微结构。结果表明:在球磨过程中粉料吸附并溶解了N2气,在后续热处理中原位反应形成了Ti2AlN相,当温度升高到一定程度时分解形成TiN,这有助于材料的致密化并使其力学性能提高。球磨粉体在1300℃、30MPa、保温、保压60min热压烧结条件下,可得到性能优异的TiN-Al2O3复合材料,该材料的抗弯强度为850MPa,断裂韧性为5.7MPa·m1/2。
The TiN/Al2O3 composites were synthesized by in situ reaction using Al and TiO2 as starting materials, which were high energy milled and hot pressed. The phase formation and transformation regularity of powders during the high energy milling process and post heat treatment were investigated by DTA, XRD and SEM with the thermodynamics calculations. Meanwhile the mechanical properties and microstructures of the composites were also studied. The results show that the N2 dissolves in the powders during the high energy milling process and the Ti2AlN phases form in the post heat treatment. When the temperature raises high enough the Ti2AlN decompose to form TiN phase, which is helpful to its densification and mechanical properties improving. TiN-Al2O3 composites with excellent properties can be fabricated by hot pressing the milled powders at 1300℃, 30 MPa and holding 60 min, whose bending strength is 850 MPa, and fracture toughness 5.7 MPa.m^1/2:
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2007年第A01期625-628,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金资助项目(50432010
50372037)
陕西科技大学科学研究基金(SUST-B14)