研究了高能球磨过程中不同添加量的硬脂酸(十八烷酸)对Ti-48at%Al粉体和材料性能的影响。利用XRD、SEM、EDS、激光粒度仪、万能力学试验机、显微硬度计分别研究了粉末的物相、形貌、球磨后的成分、粒度和烧结后Ti-48at%Al的力学性能。结果表明,当硬脂酸添加量为0wt%时,有利于Ti-48at%Al机械合金化,但粉体团聚粘壁的现象严重,偏离原始设计成分;添加量为2.5wt%时,D50为16.85μm,颗粒形貌呈不规则薄片状且均匀化程度最好、成分最接近初始成分设计。硬脂酸不同添加量的粉体经过35MPa冷压,950℃氩气保护烧结后,硬度和压缩极限强度在2wt%时达到最大值,分别为482 HV0.1和284 MPa。
Effect of different amount of stearic acid on the characteristics of Ti-48at%Al powder which prepared by high-energy ball milling was researched.The phases,particle morphology, composition and particle size of the ball milled powers were investigated by means of X-ray diffraction, scanning electron microscope, EDS and laser particle-size meter and the mechanical properties of stearic acid is Ti-48at%Al after sintering were examined by Vickers hardness tester and universal mechanical testing machine.The results indicate that when the adding amount of stearic acid is 0wt%, it benefits for mechanically alloyed of Ti-48at%Al.But the powder aggregation and stick on mill wall is serious,and it results in serious deviation of prior designed compositiion.When the stearic acid adding amount is 2.5wt%, the powder composition is nearest to the initial designed prescription,the D50 is 16.85 μm, particle appearance is irregular chip shape and uniform. When the stearic acid adding amount is 2wt%, the performances of Ti-48at%Al pieces prepared compressing at 35 MPa and sintering at 950 ℃under argon protection are that Vickers hardness can reach 482 HV0.1, the compressive strength can be 284 MPa.