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研究了机械合金化过程中Fe-Al-Ti-B四元粉体的结构演变,讨论了其合金化机制。研究表明,Fe-Al-Ti-B四元粉体的机械合金化通过Al、Ti、B原子向Fe晶格中扩散形成Fe(Al,Ti,B)过饱和固溶体。在机械合金化的早期(<10h),形成包覆结构的复合颗粒,合金化尚未进行。在机械合金化的中期(10-60h),首先形成具有几个同心圆环结构的复合颗粒,然后环状结构消失,同时Fe(Al,Ti,B)晶格常数迅速增加,但成分均匀化过程缓慢。在机械合金化的后期(60-80h),主要发生复合颗粒内部的成分均匀化过程,球磨80h后,复合颗粒内部各组元的成分已经非常均匀。Fe(Al,Ti,B)晶粒细小(6.8nm),晶格畸变严重,具有近似非晶态的结构。由于Ti、B元素的添加,Fe-Al-Ti-B四元粉体晶粒细化速率更快,但合金化速率明显降低。
The structure evolution of Fe-Al-Ti-B quaternary powder during mechanical alloying was studied and its alloying mechanism was discussed. The results show that the mechanical alloying of Fe-Al-Ti-B quaternary powders diffuses into the Fe lattice by Al, Ti, B atoms to form Fe (Al, Ti, B) supersaturated solid solution. In the early stages of mechanical alloying (<10 h), clad-structured composite particles were formed and alloying had not been performed. In the mid-period of mechanical alloying (10-60h), composite particles with several concentric ring structures are first formed, and then the ring structure disappears. At the same time, the lattice constant of Fe (Al, Ti, B) increases rapidly, The process is slow. In the late stage of mechanical alloying (60-80h), the main components of the composite particles within the homogenization process, ball milling 80h, the composition of the components within the composite particles have been very uniform. Fe (Al, Ti, B) has fine grains (6.8nm) and serious lattice distortion with an approximately amorphous structure. Due to the addition of Ti and B elements, the grain refinement rate of the Fe-Al-Ti-B quaternary powder is faster, but the alloying rate is obviously decreased.